Frequency Conversion – Hz, kHz, MHz, GHz, THz & rad/s Tools

Frequency unit conversion guide

Frequency Conversion - Hz, kHz, MHz, GHz, THz & rad/s Tools

Convert frequency units between hertz, kilohertz, megahertz, gigahertz, terahertz, revolutions per minute and radians per second. This page works as a frequency conversion hub: use the quick converter for general work, then open the dedicated RevisionTown tools when you need a focused one-way conversion such as Hz to kHz, MHz to GHz or rad/s to Hz.

Frequency Converter

Enter a value, choose the source unit, choose the target unit, and calculate. The converter uses Hz as the base unit and handles angular frequency using \(\omega=2\pi f\).

Scientific notation is accepted, such as 2.4e9.
Use 299792458 m/s for electromagnetic waves in vacuum, or enter another wave speed.

What Frequency Conversion Means

Frequency conversion means changing the unit used to express how often a repeating event occurs. A frequency of \(1\text{ Hz}\) means one cycle, oscillation, revolution, vibration or repeated event every second. A frequency of \(1000\text{ Hz}\) can also be written as \(1\text{ kHz}\). A frequency of \(1000000\text{ Hz}\) can be written as \(1\text{ MHz}\). The numerical value changes, but the physical meaning stays the same.

The most common frequency units are Hz, kHz, MHz, GHz and THz. These are all based on powers of ten. That makes the arithmetic simple if you keep the prefixes straight. The main source of error is not the formula; it is choosing the wrong power of ten. For example, \(1\text{ MHz}=1000\text{ kHz}=1000000\text{ Hz}\). A missed factor of \(1000\) can turn a radio frequency, clock rate or signal bandwidth into a completely different value.

Frequency conversion also includes angular frequency, written in radians per second. Ordinary frequency \(f\) counts cycles per second. Angular frequency \(\omega\) measures angular change per second. Since one full cycle is \(2\pi\) radians, the relationship is \(\omega=2\pi f\). This is why the conversion between Hz and rad/s is not a metric prefix conversion. It uses \(2\pi\), not \(1000\).

This page is designed as a hub. It explains the concepts, formulas and examples behind frequency conversions, while also linking to dedicated one-way tools such as the Hz to kHz converter, MHz to Hz converter and rad/s to Hz converter. Use the hub when you want understanding and comparison; use a specific converter when you already know the exact direction you need.

Frequency Units: Hz, kHz, MHz, GHz, THz and rad/s

Hertz is the SI unit of frequency. The name Hz replaces the older phrase "cycles per second." If a tuning fork vibrates 440 times per second, its frequency is \(440\text{ Hz}\). If a processor clock cycles 3.2 billion times per second, its frequency is \(3.2\text{ GHz}\). If an electromagnetic wave oscillates \(5\times 10^{14}\) times per second, its frequency may be written in terahertz.

UnitMeaningEquivalent in HzCommon use
HzHertz\(1\text{ Hz}\)Audio tones, vibration, low-frequency signals, cycles per second.
kHzKilohertz\(10^3\text{ Hz}\)Audio sampling, AM radio, ultrasonic ranges, signal bandwidths.
MHzMegahertz\(10^6\text{ Hz}\)FM radio, microcontrollers, RF communication, digital electronics.
GHzGigahertz\(10^9\text{ Hz}\)Wi-Fi, radar, microwave systems, processor clock rates.
THzTerahertz\(10^{12}\text{ Hz}\)Photonics, spectroscopy, infrared region, high-frequency science.
rad/sRadians per second\(\frac{1}{2\pi}\text{ Hz}\) per rad/sAngular frequency, circular motion, signal processing, physics equations.

The prefixes kilo, mega, giga and tera are metric prefixes. Each step from Hz to kHz to MHz to GHz to THz changes by a factor of \(1000\). Moving to a larger unit makes the number smaller. Moving to a smaller unit makes the number larger. For example, \(2.4\text{ GHz}\) is \(2400\text{ MHz}\) and \(2400000000\text{ Hz}\).

Radians per second should be treated separately. It is not a larger or smaller prefix version of Hz. It is an angular measurement. A rotating object that completes one revolution each second has a frequency of \(1\text{ Hz}\) and an angular frequency of \(2\pi\text{ rad/s}\). That distinction matters in physics, engineering, control systems, wave equations and digital signal processing.

Frequency Conversion Formulas

Most frequency conversion formulas are powers of ten. The safest method is to convert the original value to Hz first, then convert from Hz to the target unit. This avoids mixing up directions. If the starting value is in kHz, multiply by \(1000\) to get Hz. If the final value should be in MHz, divide the Hz value by \(1000000\).

Hz to kHz

\[\text{kHz}=\frac{\text{Hz}}{1000}\]

Example: \(2500\text{ Hz}=2.5\text{ kHz}\). Use the Hz to kHz converter for a focused one-step version.

kHz to Hz

\[\text{Hz}=\text{kHz}\times 1000\]

Example: \(44.1\text{ kHz}=44100\text{ Hz}\). The kHz to Hz converter is useful for audio and sampling rates.

Hz to MHz

\[\text{MHz}=\frac{\text{Hz}}{1000000}\]

Example: \(88000000\text{ Hz}=88\text{ MHz}\). For this exact direction, use the Hz to MHz converter.

MHz to Hz

\[\text{Hz}=\text{MHz}\times 1000000\]

Example: \(2.5\text{ MHz}=2500000\text{ Hz}\). See the MHz to Hz converter for fast conversions.

Hz to rad/s

\[\omega=2\pi f\]

Example: \(1\text{ Hz}=6.283185...\text{ rad/s}\). Use the Hz to rad/s converter when angular frequency is required.

rad/s to Hz

\[f=\frac{\omega}{2\pi}\]

Example: \(100\text{ rad/s}\approx 15.9155\text{ Hz}\). The rad/s to Hz converter handles this direction directly.

For very large or very small values, scientific notation keeps the conversion readable. A value such as \(3500000000\text{ Hz}\) is easier to understand as \(3.5\times 10^9\text{ Hz}\), or \(3.5\text{ GHz}\). If you need help rewriting values, the scientific notation converter can support clean formatting.

Frequency, Period and Angular Frequency

Frequency and period are reciprocal quantities. Frequency tells how many cycles happen in one second. Period tells how long one cycle takes. If a wave has frequency \(50\text{ Hz}\), it completes 50 cycles per second. The period is \(1/50=0.02\text{ s}\). If a signal has period \(0.001\text{ s}\), its frequency is \(1000\text{ Hz}\).

\[f=\frac{1}{T},\qquad T=\frac{1}{f}\]

Angular frequency is related but not identical. It describes how quickly the phase angle changes. One full cycle equals \(2\pi\) radians. Therefore a frequency of \(f\) cycles per second corresponds to angular frequency \(\omega=2\pi f\). This is why sinusoidal functions are often written as \(y=A\sin(\omega t+\phi)\) rather than \(y=A\sin(ft+\phi)\). The angle inside the sine function must be in radians.

\[\omega=2\pi f,\qquad f=\frac{\omega}{2\pi}\]

Confusing \(f\) and \(\omega\) is a common mistake. If a formula expects angular frequency in rad/s and you enter ordinary frequency in Hz, your result will be off by a factor of \(2\pi\). If a formula expects frequency in Hz and you enter rad/s, the same problem occurs in the opposite direction. Always check the symbol: \(f\) usually means frequency in Hz, while \(\omega\) usually means angular frequency in rad/s.

Frequency and Wavelength

Frequency also connects to wavelength. For a wave travelling at speed \(v\), wavelength \(\lambda\) is:

\[\lambda=\frac{v}{f}\]

This formula means that higher frequency waves have shorter wavelengths when wave speed is constant. For electromagnetic waves in vacuum, \(v\) is the speed of light, approximately \(299792458\text{ m/s}\). A \(100\text{ MHz}\) radio wave has a wavelength of about \(3\text{ m}\). A \(2.4\text{ GHz}\) Wi-Fi signal has a wavelength of about \(0.125\text{ m}\), or \(12.5\text{ cm}\).

Wavelength calculations depend on the medium. Sound in air does not travel at the speed of light. It travels much more slowly, so the wavelength for an audio tone is different from the wavelength for an electromagnetic wave at the same frequency. This is why the converter includes a wave speed field. Use the correct speed for the physical situation if you need wavelength.

Frequency conversion itself does not require wavelength, but wavelength helps interpret the number. A frequency in GHz may look abstract until you connect it to antenna size, radio band, microwave wavelength or signal propagation. In physics classes, frequency, period and wavelength often appear together, so it is useful to keep all three formulas in one place. For broader physics formula review, see basic physics equations.

Using Frequency Units in Electronics and DSP

Electronics and digital signal processing use frequency units constantly. Audio signals are often discussed in Hz and kHz. Human hearing is commonly described in the range from about \(20\text{ Hz}\) to \(20\text{ kHz}\). Audio sampling rates such as \(44.1\text{ kHz}\) and \(48\text{ kHz}\) mean samples per second, which are frequency-like rates. When converting sampling rates, it is often useful to move between kHz and Hz because formulas may require samples per second.

Microcontrollers and digital circuits often use MHz. A \(16\text{ MHz}\) clock completes 16 million cycles per second. A \(100\text{ MHz}\) oscillator completes 100 million cycles per second. Processor and wireless specifications often use GHz. A \(3.2\text{ GHz}\) clock is \(3.2\times 10^9\text{ Hz}\). The larger unit keeps the number readable.

Signal processing also uses angular frequency. Some formulas use normalized angular frequency, radians per sample, or rad/s depending on whether the system is discrete or continuous. This page focuses on rad/s and Hz, but the same principle applies: check whether the formula counts cycles, radians, seconds or samples. A unit mismatch can produce a correct-looking number with the wrong meaning.

When working with filters, oscillators, bandwidth, modulation, sampling or Fourier analysis, write the unit beside every number. If a cutoff frequency is \(2.5\text{ kHz}\), write it that way. If a formula requires Hz, convert it to \(2500\text{ Hz}\). If an equation uses \(\omega\), convert it to \(2\pi(2500)\text{ rad/s}\). This habit prevents many errors.

Using Frequency Units in Radio, Telecom and Spectrum Work

Radio and telecom systems use a wide range of frequency units. AM radio is commonly discussed in kHz, FM radio in MHz, mobile networks and Wi-Fi in MHz or GHz, radar in GHz, and optical or terahertz systems in THz. The unit is chosen to keep the number manageable. It is easier to say \(2.4\text{ GHz}\) than \(2400000000\text{ Hz}\).

A common radio conversion is MHz to Hz. For example, \(100.7\text{ MHz}=100700000\text{ Hz}\). Another common conversion is GHz to MHz. For example, \(5.8\text{ GHz}=5800\text{ MHz}\). These conversions are powers of ten, but the practical meaning is spectrum location. A mistake of \(1000\) can move a signal from one band to a completely different band.

Telecom specifications may combine frequency, bandwidth and channel spacing. A carrier frequency may be in GHz, while bandwidth may be in MHz or kHz. For example, a system may use a \(3.5\text{ GHz}\) carrier with \(100\text{ MHz}\) bandwidth. The carrier tells where the signal sits in the spectrum; the bandwidth tells how much spectrum it occupies. Both are frequency quantities, but they answer different questions.

When reading spectrum data, look for prefixes carefully. MHz and GHz differ by a factor of \(1000\). GHz and THz differ by another factor of \(1000\). If you are writing documentation, include the unit every time a value appears. If the unit is implied only once in a table heading, make sure every value in the column uses that same unit.

Worked Frequency Conversion Examples

Example 1: Hz to kHz

Convert \(2500\text{ Hz}\) to kHz.

\[\text{kHz}=\frac{2500}{1000}=2.5\text{ kHz}\]

The value becomes smaller because kHz is a larger unit than Hz.

Example 2: MHz to Hz

Convert \(88.5\text{ MHz}\) to Hz.

\[\text{Hz}=88.5\times 1000000=88500000\text{ Hz}\]

This is a common style of conversion for radio frequencies.

Example 3: GHz to MHz

Convert \(2.4\text{ GHz}\) to MHz.

\[\text{MHz}=2.4\times 1000=2400\text{ MHz}\]

This is often used for Wi-Fi and microwave frequency ranges.

Example 4: Hz to rad/s

Convert \(60\text{ Hz}\) to angular frequency.

\[\omega=2\pi(60)=120\pi\approx 376.99\text{ rad/s}\]

This conversion appears in AC circuits, oscillations and circular motion.

More Practical Examples by Field

In audio, \(440\text{ Hz}\) is a common tuning reference for the note A4. Written in kHz, it is \(0.44\text{ kHz}\). A sampling rate of \(44.1\text{ kHz}\) is \(44100\text{ Hz}\). A low-frequency vibration of \(5\text{ Hz}\) has a period of \(0.2\text{ s}\). These values are easiest to understand when the unit matches the context.

In computing, clock speeds are often written in MHz or GHz. A \(200\text{ MHz}\) clock is \(200000000\text{ Hz}\). A \(3.6\text{ GHz}\) clock is \(3600\text{ MHz}\) or \(3600000000\text{ Hz}\). The GHz form is compact, while the Hz form is sometimes needed for formulas.

In radio communication, a frequency such as \(915\text{ MHz}\) can be written as \(0.915\text{ GHz}\) or \(915000000\text{ Hz}\). A carrier at \(5.8\text{ GHz}\) is \(5800\text{ MHz}\). If an assignment asks for scientific notation, \(5.8\text{ GHz}=5.8\times 10^9\text{ Hz}\).

In angular motion, a motor rotating at \(1800\text{ RPM}\) completes 1800 revolutions per minute. Dividing by 60 gives \(30\text{ Hz}\). Multiplying by \(2\pi\) gives \(60\pi\text{ rad/s}\), or about \(188.50\text{ rad/s}\). This shows how RPM, Hz and rad/s describe related but not identical ideas.

In optics and photonics, frequencies can be extremely large. A value of \(400\text{ THz}\) is \(400000000000000\text{ Hz}\), or \(4.0\times 10^{14}\text{ Hz}\). At that scale, scientific notation is more readable than writing every zero. The THz to Hz converter is useful when converting very high-frequency values back to base SI units.

Common Mistakes in Frequency Conversion

Mixing up kilo, mega and giga

Each step is \(1000\), not \(100\). \(1\text{ GHz}=1000\text{ MHz}=1000000\text{ kHz}=1000000000\text{ Hz}\).

Treating rad/s like a metric prefix

Radians per second uses \(2\pi\), not \(1000\). Convert using \(\omega=2\pi f\) or \(f=\omega/(2\pi)\).

Forgetting period is reciprocal

Period is not another prefix unit. It is \(T=1/f\). A higher frequency means a shorter period.

Using wavelength with the wrong wave speed

Wavelength depends on speed. Electromagnetic waves in vacuum use the speed of light; sound waves in air use a much smaller speed.

Dropping units in multi-step work

Always write the unit beside the number. Many errors come from a value being copied without its unit.

Copying too many or too few digits

Use enough significant figures for the context. Engineering documentation should avoid false precision and avoid ambiguous rounded values.

If rounding and precision are part of your work, the significant figures calculator and counter can help present final answers cleanly.

How to Choose the Right Frequency Unit

The right unit is the one that makes the value easy to read and appropriate for the audience. Low-frequency events are usually written in Hz. Audio rates often use Hz or kHz. Radio frequencies often use kHz, MHz or GHz. Terahertz is used for very high frequency science and photonics. Radians per second is used when equations involve angular phase or circular motion.

For classroom answers, follow the unit requested by the question. If the question gives data in MHz and asks for Hz, convert to Hz. If it asks for angular frequency, use rad/s. If no unit is specified, choose a unit that keeps the number clear and then state it explicitly. A value of \(0.0000024\text{ THz}\) is mathematically valid, but \(2.4\text{ MHz}\) is usually clearer.

In technical documentation, consistency is often more important than compactness. A table may list every frequency in MHz even if some values are better known in GHz. This avoids comparing values with different units. If different units are used in the same document, make sure conversions are clear and avoid leaving the unit only in a heading when readers may copy values separately.

In calculations, convert to base units when formulas require it. Many physics equations assume SI units, so frequency should be in Hz and angular frequency should be in rad/s. Once the calculation is complete, convert back to a readable unit if needed. This workflow reduces errors and keeps the final answer accessible.

Frequency Conversion in Physics Learning

Frequency appears in waves, sound, light, alternating current, circular motion, simple harmonic motion and quantum ideas. Students often need to move between frequency, period, angular frequency and wavelength. This is why frequency conversion belongs naturally beside physics formula work.

In waves, frequency tells how many oscillations pass a point each second. Period tells the time for one oscillation. Wavelength tells the distance between repeated points on the wave. The formula \(v=f\lambda\) links speed, frequency and wavelength. If speed is fixed, higher frequency means shorter wavelength.

In circular motion, a rotating object can be described in revolutions per minute, cycles per second or radians per second. RPM is common for motors and mechanical systems. Hz is common for cycles per second. rad/s is common in equations. The unit you choose depends on whether you are reading a specification, performing a calculation or writing a physics model.

For students using RevisionTown physics resources, frequency conversion may sit alongside AS and A Level Physics, Cambridge IGCSE Physics and the broader physics calculator. The conversion itself is simple, but the interpretation matters in each physics context.

Frequency Conversion for RPM and Rotating Machines

Rotational speed is often written in revolutions per minute, but many equations are easier to use when the same motion is converted to Hz or rad/s. The connection is direct: one revolution is one complete cycle, and one minute contains 60 seconds. Therefore \(f=\text{RPM}/60\). A motor running at \(1800\text{ RPM}\) completes \(1800/60=30\) revolutions per second, so its frequency is \(30\text{ Hz}\).

The angular-frequency version of the same motion is \(\omega=2\pi f\). If the motor speed is \(30\text{ Hz}\), then \(\omega=2\pi\times 30=60\pi\text{ rad/s}\), which is approximately \(188.5\text{ rad/s}\). This value is common in mechanics because torque, angular acceleration, rotational kinetic energy and sinusoidal motion often use radians rather than revolutions.

RPM is convenient for specifications because it is easy to read in everyday mechanical contexts. A fan at \(1200\text{ RPM}\), a drill at \(3000\text{ RPM}\), or a spindle at \(10000\text{ RPM}\) immediately communicates speed to a technician. Hz is better when comparing cycles per second. rad/s is better when substituting into formulas. A careful solution can show all three: \(3000\text{ RPM}=50\text{ Hz}=100\pi\text{ rad/s}\).

When converting rotating-machine values, do not confuse the electrical frequency with the mechanical shaft frequency. An AC supply may be \(50\text{ Hz}\) or \(60\text{ Hz}\), but a motor shaft may rotate at a different speed depending on the motor type, pole count, load and slip. If a problem gives shaft RPM, convert that RPM directly. If it gives AC line frequency, use the motor relationship specified in the problem instead of assuming the shaft speed is identical.

The calculator on this page includes RPM so you can move quickly between rotational speed, Hz and rad/s. If the task is specifically angular frequency, the dedicated rad/s to Hz converter and Hz to rad/s converter give a narrower one-direction workflow.

Prefix and Scientific Notation Checks

Most mistakes in frequency conversion come from losing a group of three zeros. Metric prefixes are based on powers of ten, and the frequency prefixes on this page move in steps of \(10^3\): \(1\text{ kHz}=10^3\text{ Hz}\), \(1\text{ MHz}=10^6\text{ Hz}\), \(1\text{ GHz}=10^9\text{ Hz}\), and \(1\text{ THz}=10^{12}\text{ Hz}\). Each step up the prefix ladder divides the displayed number by 1000. Each step down multiplies it by 1000.

A reliable check is to write the value in scientific notation first. Suppose a signal is \(725000000\text{ Hz}\). In scientific notation this is \(7.25\times 10^8\text{ Hz}\). Since \(1\text{ MHz}=10^6\text{ Hz}\), divide by \(10^6\): \(7.25\times 10^8 / 10^6 = 7.25\times 10^2 = 725\text{ MHz}\). Since \(1\text{ GHz}=10^9\text{ Hz}\), divide by \(10^9\): \(7.25\times 10^8 / 10^9 = 0.725\text{ GHz}\). Both answers are equivalent.

Scientific notation is also useful when the result contains a long decimal. For example, \(0.000000045\text{ GHz}\) is correct, but it is not a helpful final answer for most readers. The same value is \(45\text{ Hz}\). A good unit choice should reduce visual clutter without hiding the scale. A value of \(45000\text{ Hz}\) can be written as \(45\text{ kHz}\); a value of \(45000000\text{ Hz}\) can be written as \(45\text{ MHz}\).

When checking a conversion, ask whether the new number became larger or smaller for the right reason. Converting from Hz to kHz should make the numeric value smaller because kHz is a larger unit. Converting from GHz to Hz should make the numeric value much larger because Hz is a smaller unit. If \(2.4\text{ GHz}\) becomes \(0.0000000024\text{ Hz}\), the direction has been reversed. The correct conversion is \(2.4\text{ GHz}=2.4\times 10^9\text{ Hz}\).

For written solutions, keep the exponent attached to the unit. Write \(3.2\times 10^6\text{ Hz}\), not just \(3.2\times 10^6\). A number without a unit is hard to audit. When final answers require a fixed number of significant figures, convert first, then round at the end. Rounding too early can change later values, especially when the frequency is used to compute period, wavelength or angular frequency.

Bandwidth, Carrier Frequency and Sampling Frequency

Frequency conversion is not only about changing labels; it also helps separate different meanings of frequency. In communications, the carrier frequency is the central oscillation used to transmit a signal, while bandwidth describes the range of frequencies occupied by the information. A carrier might be \(2.4\text{ GHz}\), while a channel bandwidth might be \(20\text{ MHz}\). These are both frequency values, but they answer different questions.

Converting both values to the same unit makes comparisons clearer. A \(2.4\text{ GHz}\) carrier is \(2400\text{ MHz}\). A \(20\text{ MHz}\) bandwidth is much smaller than the carrier frequency, even though both may appear in the same device specification. If a reader compares \(2.4\) and \(20\) without noticing the units, they may draw the wrong conclusion. Always normalize units before comparing magnitudes.

Sampling frequency is another common frequency value. In digital audio, \(44.1\text{ kHz}\) means a waveform is sampled 44100 times per second. In measurement systems, a sampling rate might be given in kHz, MHz or samples per second. A conversion may be required before using a timing formula. If the sampling frequency is \(f_s=100\text{ kHz}\), the sampling period is \(T_s=1/f_s=1/100000=0.00001\text{ s}\), or \(10\text{ microseconds}\).

The same logic applies in data acquisition and digital signal processing. If a signal frequency is \(5\text{ kHz}\) and a sampling frequency is \(50\text{ kHz}\), converting both to Hz gives \(5000\text{ Hz}\) and \(50000\text{ Hz}\). The sampling frequency is ten times the signal frequency. The conversion is simple, but the interpretation is important: the ratio between frequencies often matters more than the absolute unit used to display them.

Angular frequency can appear in signal-processing formulas, especially when using sinusoidal models such as \(x(t)=A\sin(\omega t+\phi)\). If the ordinary frequency is \(f=1000\text{ Hz}\), the angular frequency is \(\omega=2\pi\times 1000=2000\pi\text{ rad/s}\). If a formula is written using \(\omega\), do not substitute \(1000\) directly unless the formula explicitly expects Hz. Use the angular value in rad/s.

When a specification mixes carrier frequency, bandwidth, sampling rate and angular frequency, treat each value separately. Convert the carrier to the most readable radio unit, often MHz or GHz. Convert bandwidth to the unit used by the system table, often kHz or MHz. Convert sampling rate to Hz before finding sampling period. Convert ordinary frequency to rad/s only when the formula uses angular frequency. This prevents one type of frequency from being mistaken for another.

When to Use This Hub and When to Use a Dedicated Converter

This frequency conversion page is built as a broad reference and multi-unit calculator. Use it when you want to compare several units, understand the formulas, check related quantities such as period or wavelength, or decide whether Hz, kHz, MHz, GHz, THz, RPM or rad/s is the clearest final unit. It is especially useful when a problem combines more than one relationship, such as \(T=1/f\), \(\lambda=v/f\), and \(\omega=2\pi f\).

Use a dedicated converter when the task is narrow and repetitive. If you are only converting Hz to MHz values, the Hz to MHz converter is faster because it focuses on that one direction. If you are checking radio values from MHz to GHz, the MHz to GHz converter keeps the workflow simple. If you are converting processor or microwave values back to base units, the GHz to Hz converter is the better focused page.

The hub and the one-way tools serve different reader intents. A learner may need the hub to understand why \(1\text{ MHz}=1000000\text{ Hz}\) and why \(1\text{ Hz}=2\pi\text{ rad/s}\). A technician may only need a fast directional calculator. A teacher may use the hub for examples and formulas, then link students to a dedicated converter for practice. Keeping those purposes separate makes the content easier to use.

For site navigation, start with this page when the target unit is not yet clear. Move to a dedicated page when the direction is known. Move to the advanced frequency conversion tool when you need a wider range of frequency units. Move to the unit conversion calculator chart when frequency is only one part of a larger unit-conversion task.

Frequency Conversion Reference Table

ConversionFormulaExampleBest use
Hz to kHz\(\text{kHz}=\text{Hz}/1000\)\(5000\text{ Hz}=5\text{ kHz}\)Audio tones, low-frequency electronics.
kHz to MHz\(\text{MHz}=\text{kHz}/1000\)\(2500\text{ kHz}=2.5\text{ MHz}\)Radio bands, signal bandwidths.
MHz to GHz\(\text{GHz}=\text{MHz}/1000\)\(2400\text{ MHz}=2.4\text{ GHz}\)Wi-Fi, microwave, processor rates.
GHz to Hz\(\text{Hz}=\text{GHz}\times 10^9\)\(3.5\text{ GHz}=3.5\times 10^9\text{ Hz}\)SI unit calculations.
THz to Hz\(\text{Hz}=\text{THz}\times 10^{12}\)\(0.4\text{ THz}=4\times 10^{11}\text{ Hz}\)High-frequency science.
Hz to rad/s\(\omega=2\pi f\)\(10\text{ Hz}=20\pi\text{ rad/s}\)Angular frequency in equations.

This table is a quick reference, but the concept is always the same: convert metric prefixes using powers of ten and convert angular frequency using \(2\pi\). For angle-unit context, the advanced angle converter, degrees to radians converter and radians to degrees converter can help when the same problem mixes cycles, radians and degrees.

Step-by-Step Method for Any Frequency Conversion

A dependable method is better than memorizing every possible pair. First, identify the starting unit and the target unit. Second, convert the starting value to Hz, unless the conversion is directly between Hz and rad/s. Third, convert from Hz to the final unit. Fourth, check whether the final value became larger or smaller in the expected direction. This four-step method works for Hz, kHz, MHz, GHz, THz, RPM and rad/s.

For example, convert \(0.0035\text{ GHz}\) to kHz. Start with GHz. Convert to Hz: \(0.0035\text{ GHz}=0.0035\times 10^9\text{ Hz}=3500000\text{ Hz}\). Then convert Hz to kHz: \(3500000\text{ Hz}/1000=3500\text{ kHz}\). The answer is \(3500\text{ kHz}\). The number grew from \(0.0035\) to \(3500\) because kHz is a much smaller unit than GHz.

For a rad/s example, convert \(125.66\text{ rad/s}\) to Hz. Use \(f=\omega/(2\pi)\). The result is approximately \(125.66/6.283185=20.0\text{ Hz}\). If you also need RPM, multiply Hz by 60: \(20.0\times 60=1200\text{ RPM}\). This shows why rad/s, Hz and RPM often appear together in circular motion and rotating equipment problems.

For a wavelength example, suppose a wave travels at \(340\text{ m/s}\) and has a frequency of \(2\text{ kHz}\). Convert \(2\text{ kHz}\) to \(2000\text{ Hz}\), then use \(\lambda=v/f\). The wavelength is \(340/2000=0.17\text{ m}\). If the same frequency were an electromagnetic wave in a vacuum, the speed would be approximately \(3.00\times 10^8\text{ m/s}\), and the wavelength would be much longer for the same frequency. The frequency conversion is unchanged, but the physical interpretation changes with wave speed.

For exam-style work, show the unit conversion before the final substitution. A clear line such as \(4.8\text{ MHz}=4.8\times 10^6\text{ Hz}\) makes the next step easier to audit. It also prevents a common mistake: placing a value given in MHz directly into a formula that expects Hz. The arithmetic may still look tidy, but the answer will be wrong by a factor of one million.

Typical Frequency Ranges and What the Units Suggest

Units often hint at the scale of a problem. Hz is common for slow cycles, mains electricity, mechanical vibration, musical pitch and basic wave calculations. A value such as \(50\text{ Hz}\) or \(60\text{ Hz}\) is easy to read directly. If a value is \(0.05\text{ kHz}\), it may be mathematically correct, but \(50\text{ Hz}\) is usually clearer. The best unit is not always the largest or shortest; it is the one that communicates the scale with the least confusion.

kHz is common in audio, ultrasound entry points, radio bandwidths and microcontroller timing. Human hearing is often discussed from about \(20\text{ Hz}\) to \(20\text{ kHz}\). Digital audio sampling rates such as \(44.1\text{ kHz}\) and \(48\text{ kHz}\) are also familiar. When converting audio-related values, be careful not to confuse signal frequency with sampling frequency. A \(1\text{ kHz}\) tone is not the same thing as a \(44.1\text{ kHz}\) sample rate.

MHz is common for many radio, electronics and clock-frequency contexts. Older processor speeds, microcontroller clocks, FM radio frequencies and intermediate-frequency stages often use MHz. A value of \(100\text{ MHz}\) is \(100000000\text{ Hz}\). In formulas, the base SI value may be required, but in specifications MHz is often much easier to scan.

GHz is common for modern wireless systems, microwave frequencies, radar, processor clock labels and high-speed electronics. Wi-Fi bands, cellular bands and microwave equipment often use GHz because writing the same values in Hz would create long strings of zeros. For example, \(5.8\text{ GHz}=5800000000\text{ Hz}\). In a short product table, \(5.8\text{ GHz}\) is far more readable than the full Hz value.

THz is used for very high-frequency science, spectroscopy, photonics and some advanced communications research. Because \(1\text{ THz}=10^{12}\text{ Hz}\), values can become extremely large when converted to Hz. At this scale, scientific notation is not only convenient; it is often necessary for clarity. Writing \(4.3\times 10^{14}\text{ Hz}\) is easier to review than writing hundreds of trillions of cycles per second as a plain integer.

rad/s appears when a problem is modeled through angular phase, oscillation or circular motion. The unit does not replace Hz; it describes the same repeating behavior in angular terms. If a formula uses \(\sin(\omega t)\), \(\omega\) must be in rad/s so that the angle inside the sine function is measured correctly. If a formula uses cycles per second, ordinary frequency in Hz is the right quantity.

Frequency Conversion for Period, Timing and Delay

Frequency and period are reciprocals. This means that after converting a frequency into Hz, the period is \(T=1/f\). A \(1\text{ Hz}\) signal has a period of \(1\text{ s}\). A \(10\text{ Hz}\) signal has a period of \(0.1\text{ s}\). A \(1\text{ kHz}\) signal is \(1000\text{ Hz}\), so its period is \(0.001\text{ s}\), or \(1\text{ ms}\). A \(1\text{ MHz}\) clock is \(1000000\text{ Hz}\), so its period is \(0.000001\text{ s}\), or \(1\text{ microsecond}\).

Timing calculations are a useful way to catch unit mistakes. If a processor clock is \(100\text{ MHz}\), the period should be very small: \(1/(100\times 10^6)=10^{-8}\text{ s}\), or \(10\text{ ns}\). If a calculation gives \(0.01\text{ s}\), the value was probably treated as \(100\text{ Hz}\) rather than \(100\text{ MHz}\). The reciprocal relationship magnifies prefix mistakes, so converting to Hz first is important.

Delay and sampling problems often require moving between frequency and time. If a sampling rate is \(2\text{ kHz}\), samples are taken every \(1/2000\text{ s}=0.0005\text{ s}\), or \(0.5\text{ ms}\). If a control loop updates every \(5\text{ ms}\), its update frequency is \(1/0.005=200\text{ Hz}\). These are not separate ideas; they are two ways of describing the same repeated timing.

For periodic motion, the same approach applies. A pendulum with period \(0.8\text{ s}\) has frequency \(1/0.8=1.25\text{ Hz}\). The angular frequency is then \(2\pi\times 1.25=2.5\pi\text{ rad/s}\). In simple harmonic motion, the angular value may be the quantity used in equations, while the ordinary frequency may be easier to interpret physically.

When reporting period from frequency, choose a time unit that is readable. For low frequencies, seconds may be fine. For kHz, milliseconds or microseconds may be better. For MHz and GHz, microseconds, nanoseconds or picoseconds may be more appropriate. The frequency calculator gives period in seconds as a base value, but the reader may prefer a scaled time unit in written explanations.

Quality Checks Before Publishing or Submitting an Answer

Before using a converted frequency in a report, assignment, design note or calculator result, perform a few quick quality checks. The first check is direction: did the number move the right way when the unit changed? The second check is scale: does the converted value match the physical context? The third check is notation: is the final value readable and not overloaded with unnecessary zeros?

The fourth check is formula compatibility. If a formula expects \(f\), use Hz unless the formula states otherwise. If it expects \(\omega\), use rad/s. If it expects period, use seconds. If it expects wavelength, make sure the wave speed is known and expressed in compatible units. A correct frequency conversion can still lead to a wrong answer if the next formula uses a different quantity.

The fifth check is rounding. Keep enough digits during intermediate steps, then round the final answer to the precision required by the problem or data. If the input is \(2.400\text{ GHz}\), the trailing zeros may indicate measurement precision. If the input is \(2.4\text{ GHz}\), reporting \(2400000000.000000\text{ Hz}\) creates false precision. A sensible final answer might be \(2.4\times 10^9\text{ Hz}\) unless the task asks for a specific decimal format.

The sixth check is unit visibility. In a table, put units in column headings and keep them consistent. In a worked solution, write the unit beside each line. In calculator output, include both the converted unit and the base Hz value when possible. This is especially helpful on a hub page because users may enter values in one unit, convert to another, and then use the result in a formula that needs Hz.

Finally, check whether a dedicated tool would be clearer for the reader. A broad hub is helpful for explanation and comparison, but a one-direction calculator can be easier for quick conversions. Linking from the hub to the exact converter direction helps readers continue without forcing every page to cover the same intent.

Frequently Asked Questions

What is the base unit of frequency?

The SI base-derived unit for frequency is hertz, written Hz. \(1\text{ Hz}=1\text{ s}^{-1}\), meaning one cycle per second.

How do I convert kHz to Hz?

Multiply by 1000. For example, \(12.5\text{ kHz}=12500\text{ Hz}\).

How do I convert MHz to GHz?

Divide by 1000. For example, \(2400\text{ MHz}=2.4\text{ GHz}\).

How do I convert GHz to MHz?

Multiply by 1000. For example, \(5.8\text{ GHz}=5800\text{ MHz}\).

Is rad/s the same as Hz?

No. Hz counts cycles per second. rad/s measures angular frequency. The relationship is \(\omega=2\pi f\).

What is 1 Hz in rad/s?

\(1\text{ Hz}=2\pi\text{ rad/s}\), which is approximately \(6.283185\text{ rad/s}\).

What is the period of a 50 Hz signal?

Use \(T=1/f\). For \(50\text{ Hz}\), \(T=1/50=0.02\text{ s}\), or 20 ms.

Why are frequency values sometimes written in scientific notation?

Scientific notation keeps very large or very small values readable. For example, \(2400000000\text{ Hz}\) is easier to read as \(2.4\times 10^9\text{ Hz}\).

Final Frequency Conversion Checklist

Before finalizing a conversion, identify whether you are working with ordinary frequency, angular frequency, period, wavelength or rotational speed. Convert metric frequency units through Hz using powers of ten. Convert Hz and rad/s using \(2\pi\). Convert frequency and period using reciprocals. Convert frequency and wavelength only when the wave speed is known.

Keep units visible at every step. Write \(2.4\text{ GHz}=2400\text{ MHz}=2.4\times 10^9\text{ Hz}\), not just \(2.4=2400=2400000000\). Use scientific notation for very large values, and choose a final unit that fits the context. A clear conversion is not only mathematically correct; it is readable, traceable and hard to misinterpret.