Voltage Conversion Calculator: V, mV, µV, kV, MV & GV

Physics & electronics · Voltage units

Voltage Conversion, One Clear Scale

Instantly convert voltage units—volts, microvolts, millivolts, kilovolts, megavolts and gigavolts—for scientific, electrical or academic needs.

Choose a converter, understand the power-of-ten rule, and check your answer with worked examples.

Use the voltage converter ↓
A digital multimeter, insulated probes and a small battery holder on an electronics study bench.
Choose a convenient unit for the same voltage—from small sensor signals to larger-scale calculations.

Voltage Unit Converter

Enter a value and choose its starting and target units. Negative values are supported; a negative sign records polarity relative to a chosen reference.

Use a decimal or scientific notation, such as 2.5e-3. Enter the number without commas or a unit.

Results display up to 12 significant digits. SI prefix factors are exact; changing the unit does not change the physical voltage.

Metric Prefix & High-Voltage Converters

Choose from ten voltage conversion tools below. Each card shows the direction and scaling rule; the dedicated page provides that conversion.

Volts to Microvolts (µV)

Convert volts to microvolts for sensitive signal work.

1 V =106 μV
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Volts to Millivolts (mV)

Switch V to mV for electronics, labs, or low-voltage circuits.

1 V =103 mV
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Volts to Kilovolts (kV)

Power transmission and utilities conversion.

1 V =10−3 kV
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Volts to Megavolts (MV)

Express volts in megavolts for specialist high-voltage calculations. Check the actual unit used in an industrial or grid specification.

1 V =10−6 MV
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Volts to Gigavolts (GV)

Convert volts to gigavolts for specialist scientific or engineering calculations; GV is not a usual everyday power-plant unit.

1 V =10−9 GV
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Microvolts (µV) to Volts

Ultra-small signals to volts measurement.

1 μV =10−6 V
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Millivolts (mV) to Volts

Express millivolt readings in volts, including values below one volt.

1 mV =10−3 V
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Kilovolts (kV) to Volts

Convert power transmission voltage to standard volts.

1 kV =103 V
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Megavolts (MV) to Volts

Express megavolt values in volts, preserving the value stated in the original specification.

1 MV =106 V
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Gigavolts (GV) to Volts

Calculate GV to V for scientific or engineering specs.

1 GV =109 V
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What Is Voltage?

Voltage is electric potential difference: energy transferred per unit charge between two points. Its SI unit is the volt, with symbol V.

1 V =1 J/C

Using positive magnitudes for the energy transfer E and nonzero charge Q, the potential-difference magnitude is V =E/Q. A voltage of five volts corresponds to five joules per coulomb of charge.

Units such as millivolts and kilovolts describe the same quantity at different scales. Converting units changes the number and unit together, while the measured potential difference remains the same.

Voltage Prefixes at a Glance

Read the letter case carefully: micro, milli, kilo, mega and giga represent different powers of ten.

All factors are exact SI prefix definitions
UnitSymbolOne unit in voltsOne volt expressed in this unit
microvoltμV10−6 V106 μV
millivoltmV10−3 V103 mV
voltV100 V100 V
kilovoltkV103 V10−3 kV
megavoltMV106 V10−6 MV
gigavoltGV109 V10−9 GV
  1. µVmicrovolt10−6 V
  2. mVmillivolt10−3 V
  3. Vvolt100 V
  4. kVkilovolt103 V
  5. MVmegavolt106 V
  6. GVgigavolt109 V
Each step toward a larger unit makes the numerical value 1,000 times smaller. Going toward a smaller unit makes the number 1,000 times larger.

Microvolts and millivolts are convenient for small signals; kilovolts are often used for power-system specifications. Megavolts and gigavolts are much larger scales, used in specialist contexts or calculations; they are not interchangeable with ordinary power-plant or grid unit labels.

The Voltage Conversion Formula

Use volts as a bridge. If the source unit is 10a volts and the target unit is 10b volts, multiply the numerical value by the difference in powers:

xtarget =xsource×10a−b

For example, from millivolts to kilovolts, a =−3 and b =3, so the factor is 10−6.

2500 mV =2500×10−6 kV =0.0025 kV
  1. Write the original value with its unit.
  2. Identify each unit's exponent relative to volts.
  3. Subtract the target exponent from the source exponent.
  4. Multiply by that power of ten and attach the target unit.
  5. Check the direction: a larger unit should produce a smaller numerical magnitude.

Adding and subtracting voltages requires a common unit. For example, 2 V +500 mV =2 V +0.5 V =2.5 V.

Worked Voltage Conversion Examples

1. Volts to millivolts

Because one volt is one thousand millivolts, multiply by one thousand:

3.3 V =3.3×1000 mV =3300 mV

The smaller unit produces a larger number. Try the V to mV tool.

2. Microvolts to volts

One microvolt is one millionth of a volt:

750 μV =750×10−6 V =0.00075 V

The same value is 0.75 mV. Scientific notation is 7.5×10−4 V.

3. Kilovolts to volts

Multiply by one thousand:

11 kV =11×103 V =11000 V

Writing the value in volts does not physically increase the voltage. Check the kV to V tool.

4. Volts to megavolts

Divide by one million:

250000 V =250000×10−6 MV =0.25 MV

Keep the upper-case M: 0.25 mV would be a completely different value.

A negative-voltage example

−12 V =−12000 mV

The prefix factor is positive, so the polarity sign stays negative. Prefix conversion does not change the reference point.

Common Voltage Conversion Mistakes

Check the unit, the direction and the type of voltage
Common mix-upWhat to check
mV versus MVLower-case m is milli; upper-case M is mega. 1 MV =109 mV.
Multiplying in the wrong directionConverting V to kV divides by one thousand. Converting kV to V multiplies by one thousand.
Confusing volts and wattsVoltage and power are different quantities. A voltage unit conversion cannot determine power without more information.
Confusing µV and uVµV is the microvolt symbol. uV is sometimes used as a plain-text substitute, but the calculator and table use µV.
Mixing RMS, peak and peak-to-peakA prefix conversion preserves the type of value. Converting mV RMS to V still gives an RMS value.

AC and DC use the same voltage units

Both AC and DC voltages may be expressed in volts or prefixed volts. Prefix conversion alone does not convert one waveform or measurement convention into another.

For a pure, zero-centred sinusoidal voltage, separate waveform relationships are VRMS =Vpeak/2 and Vpp =2Vpeak. These factors are not general rules for every waveform. For instance, a reading of 1000 mV RMS becomes 1 V RMS by unit conversion alone.

Check Your Understanding

Convert 48,000 mV to volts.

Divide by one thousand: 48000 mV =48 V. The unit is larger, so the number becomes smaller.

Convert 0.002 kV to millivolts.

First convert to volts: 0.002 kV =2 V. Then 2 V =2000 mV. The combined factor is 106.

Are 5 mV and 5 MV equal?

No. 5 mV =0.005 V, while 5 MV =5000000 V. The second magnitude is one billion times the first.

Voltage Conversion FAQs

How many millivolts are in one volt?

1 V =1000 mV. Multiply a numerical value in volts by one thousand to express it in millivolts.

How do I convert millivolts to microvolts?

1 mV =1000 μV. Multiply by one thousand, or use the quick converter above.

How many volts are in one kilovolt?

1 kV =1000 V. The prefix kilo means one thousand.

Does changing the unit change electrical energy or power?

No. Re-expressing a voltage leaves the physical situation unchanged. Calculating energy also needs charge or other circuit information; calculating power also needs current or other appropriate information.

Is voltage the same as electric potential difference?

In this context, voltage means potential difference between two points, measured in volts. Always identify the reference points when interpreting a signed reading.