i-Ready vs CAASPP

i-Ready and CAASPP may both appear on a California student’s assessment calendar, but they are not two versions of the same test. i-Ready Inform—called i-Ready Diagnostic before the 2026–2027 school year—is a school-selected adaptive assessment designed mainly to help educators understand current skills, plan instruction, and set individualized growth goals. CAASPP is California’s statewide assessment system. Its Smarter Balanced summative tests measure how well students in Grades 3–8 and Grade 11 have learned California’s grade-level English language arts/literacy and mathematics standards.

That difference in purpose explains why the reports look so different. An i-Ready report may show a scale score, grade-level placement, percentile rank, domain performance, Typical Growth, and Stretch Growth. A CAASPP Smarter Balanced Student Score Report shows a separate overall scale score for ELA and mathematics, one of four achievement levels, performance-area information, and—when available—score history. Starting with 2025–2026 results, California renamed the four levels Advanced, Proficient, Developing, and Minimal. The underlying cut scores did not change.

The most important rule is simple: do not directly convert an i-Ready score into a CAASPP score. A 500, 550, or 600 on i-Ready is not automatically equal to a particular four-digit CAASPP score or achievement level. The assessments use different scales, blueprints, testing schedules, and reporting purposes. This guide explains how to read both results responsibly and how parents and educators can use them together.

i-Ready vs CAASPP at a glance

What is i-Ready Inform?

i-Ready Inform is Curriculum Associates’ computer-adaptive Reading and Mathematics assessment for Grades K–12. It was known as i-Ready Diagnostic for many years. Curriculum Associates announced that the name would change to i-Ready Inform beginning in the 2026–2027 school year to emphasize the assessment’s main job: providing information that guides learning. Families may still hear teachers, portals, and older documents use “Diagnostic,” so the two names will overlap for a while.

During an adaptive assessment, the system selects later questions partly from the student’s earlier responses. A correct response may lead to a more challenging item, while an incorrect response may lead to a less difficult one. Students should therefore expect some questions that feel easy, some that feel appropriately challenging, and some they have not yet learned. Reaching unfamiliar material is part of how the assessment locates the boundaries of current knowledge; it does not mean a student is failing.

Schools commonly give i-Ready near the beginning, middle, and end of the year. The report is intended to support decisions while instruction is still happening. Teachers can examine the overall result, grade-level placement, and skill domains to identify likely strengths and needs. They can then combine the report with classwork, observation, curriculum assessments, and other evidence before choosing lessons or intervention.

If your report uses unfamiliar terminology, start with RevisionTown’s complete explanation of i-Ready Inform and the guide to reading every number on an i-Ready report.

What is CAASPP?

CAASPP stands for the California Assessment of Student Performance and Progress. It is an assessment system rather than a single test. For many families, “CAASPP” refers mainly to the Smarter Balanced Summative Assessments in English language arts/literacy and mathematics, but the wider system includes additional assessments.

• Smarter Balanced Summative Assessments: ELA and mathematics for Grades 3–8 and Grade 11.
• California Science Test (CAST): Science in Grades 5 and 8 and once in high school.
• California Alternate Assessments (CAAs): Alternate assessments for eligible students whose individualized education programs identify the appropriate assessment.
• California Spanish Assessment (CSA): An assessment of reading/language arts in Spanish for eligible or interested students under California’s participation rules.

This article compares i-Ready Reading and Mathematics with the general Smarter Balanced CAASPP ELA and mathematics tests. CAST, CAA, and CSA scores have their own designs and reporting scales. They should not be mixed into an i-Ready comparison as though every CAASPP test produces the same type of result.

Who takes i-Ready and who takes CAASPP?

i-Ready participation depends on local adoption. A district, charter school, or individual school may purchase and use i-Ready, and another California school may use a different interim or diagnostic assessment. Curriculum Associates offers i-Ready Inform for Grades K–12, but that does not mean every student in those grades takes it.

Smarter Balanced CAASPP participation is organized by state-tested grade. Students take the general ELA and mathematics summative assessments in Grades 3, 4, 5, 6, 7, 8, and 11 unless an applicable participation rule or alternate-assessment decision applies. A second grader may have an i-Ready Reading score but no Smarter Balanced summative score yet. A ninth or tenth grader may use i-Ready locally but generally will not take the Smarter Balanced summative ELA and math tests until Grade 11.

This grade difference matters when parents compare siblings or search for score charts. A score chart for one program cannot fill a grade where the other program is not administered. It is also why “What CAASPP level equals my child’s i-Ready score?” is often the wrong first question. Begin with the student’s grade, subject, test date, and exact assessment name.

When are the assessments given?

i-Ready is usually used during three local windows: fall, winter, and spring. The precise dates are selected by the school or district. A fall score is a beginning-of-year instructional snapshot; a spring score reflects a later point after months of instruction. Because national norms and grade-level expectations are season-aware, families should compare results using the correct testing window.

CAASPP Smarter Balanced is an annual summative assessment. California local educational agencies select their exact window within state rules. Official CAASPP guidance says summative testing does not begin until 66 percent of a school’s annual instructional days are complete and may continue through the last day of school, no later than June 30. The local window must meet California’s requirements, so families should use their district or school calendar for exact dates rather than assuming one statewide test week.

The timing creates a practical distinction. Fall or winter i-Ready results can help a teacher make adjustments before the annual CAASPP window. CAASPP then provides an end-of-year standards-based result. One is not merely practice for the other; they are evidence collected at different points for different decisions.

How the adaptive designs compare

Both systems use computer-adaptive technology, but “adaptive” does not mean identical. i-Ready adapts within its own item bank and test flow to estimate a student’s Reading or Mathematics achievement and provide placement and domain information. The goal is an efficient instructional picture across a broad span of skills.

The Smarter Balanced summative assessment has two major components: a computer-adaptive test, usually abbreviated CAT, and a performance task, abbreviated PT. The adaptive component selects questions while satisfying the content requirements in the official blueprint. The performance task asks students to apply multiple skills to a connected problem or set of sources. In ELA, that can involve reading, research, and an extended written response. In mathematics, it can require reasoning, modeling, and explanation rather than only choosing an answer.

Because the CAASPP score reflects required blueprint content and a performance task, a short diagnostic-style quiz cannot reproduce the full testing experience. Likewise, CAASPP’s annual design is not intended to deliver the same day-to-day instructional grouping recommendations as i-Ready. The word “adaptive” describes part of how items are delivered; it does not make the scores interchangeable.

Testing time: i-Ready vs CAASPP

i-Ready completion time varies with grade, subject, pace, and the 2026–2027 assessment design. Schools often plan approximately 30–60 minutes per subject, sometimes split across more than one session. Younger students may need shorter sessions. The assessment should not be rushed simply to meet a class average; unusual speed can reduce the usefulness of the instructional estimate.

The official California CAASPP page describes the Smarter Balanced content-area assessments as taking approximately five to six hours and notes that they are untimed. Schools normally divide testing into sessions, and individual students may need more or less time. The CAT and performance-task portions also place different demands on attention. Families should rely on the school schedule rather than expecting a student to complete all ELA and mathematics testing in one sitting.

Time alone is not a score. A fast student can perform accurately, and a careful student can need longer. The useful question is whether the student worked steadily, read directions, used available tools appropriately, and had a reasonable testing environment.

i-Ready scores explained

i-Ready scale score

The i-Ready scale score is the central number produced by the adaptive assessment. It places performance on i-Ready’s continuous scale so educators can compare results across administrations. The same number must still be interpreted in context: Reading and Mathematics are separate, grade matters, and fall, winter, and spring expectations are not identical.

Grade-level placement

Placement translates the scale score into a criterion-referenced description relative to the student’s enrolled grade. The report may describe performance as above grade level, on grade level, one grade level below, or two or more grade levels below, with more detailed five-level placement language in current resources. Placement is more understandable than the raw score, but it is an instructional signal—not a new grade assignment and not a statement about intelligence.

Percentile rank

The percentile rank compares the student’s performance with a nationally representative group of students in the same grade who tested at a similar time of year. The 60th percentile means the score was as high as or higher than approximately 60 percent of students in that comparison group; it does not mean 60 percent of questions were correct.

Typical Growth and Stretch Growth

Typical Growth is an individualized annual growth benchmark based on students with a similar starting point. Stretch Growth is a more ambitious target designed to support movement toward or beyond grade-level proficiency. These are i-Ready-specific growth concepts. CAASPP does not report a student’s Typical Growth or Stretch Growth percentage.

Domain results

i-Ready breaks the subject into instructional domains. Reading can include Phonological Awareness, Phonics, High-Frequency Words, Vocabulary, and comprehension of literature and informational text, depending on grade and test flow. Mathematics commonly includes Number and Operations, Algebra and Algebraic Thinking, Measurement and Data, and Geometry. Domain placements help teachers decide what to teach next, but small differences should not be treated as perfectly precise rankings.

CAASPP scores explained

Overall scale score

A Smarter Balanced Student Score Report gives an overall four-digit scale score for each tested subject. It is built from the student’s pattern of responses across the CAT and performance task. The number belongs to the Smarter Balanced scale, not the i-Ready scale.

Possible score ranges differ by grade and subject. For example, California’s 2025–2026 Grade 5 sample report displays an ELA score range of 2200–2730 and a mathematics range of 2220–2740. Those ranges illustrate the scale; they are not “good score” targets and should not be applied to another grade. A family should use the achievement level and narrative printed on the student’s actual report.

Achievement Level

California reports four overall achievement levels for Smarter Balanced ELA and mathematics. Beginning with 2025–2026 results, the labels are:

The California Department of Education states that the criteria and cut scores did not change when the labels changed. Therefore, a 2024–2025 Level 3 “Standard Met” result and a 2025–2026 Level 3 “Proficient” result use different words for the same level structure. Families comparing years should focus on the level number, scale score, and grade-specific standard—not assume that the new label created an easier or harder test.

Performance areas

The report also gives broader information within each subject. The current area-reporting labels are Above Proficient, At or Near Proficient, and Below Proficient. In the 2025–2026 sample family report, ELA information is grouped into Reading and Listening plus Writing and Research. Mathematics reporting addresses concepts and procedures along with problem solving, modeling/data analysis, and communicating reasoning.

Area results are less precise than the overall score and should be treated as broad evidence. California’s family report encourages combining assessment results with other information. A single “Below Proficient” area is a reason to look at classwork and talk with the teacher, not a complete diagnosis by itself.

Score history

When prior results are available, the Student Score Report may show a score history across tested grades. The report reminds families that next-grade standards are higher. A student may increase the scale score yet remain at the same achievement level because the standard rises with grade-level expectations. Conversely, moving to a higher level indicates that improvement was enough to cross that grade’s level boundary.

Can you convert an i-Ready score to a CAASPP score?

No universal conversion should be published or trusted. Statements such as “550 i-Ready equals 2500 CAASPP” or “the 70th i-Ready percentile guarantees CAASPP Level 4” oversimplify two different measurement systems. The same i-Ready score can have a different meaning by grade, subject, and season. CAASPP cut scores also differ by grade and subject.

Curriculum Associates reports that i-Ready is highly correlated with many state summative assessments. Correlation can support prediction at a group level, but it does not turn two scales into the same ruler. Even a strong statistical relationship includes uncertainty. A prediction study must identify the assessment version, state, grade, subject, testing season, sample, and outcome. Without a validated California-specific linking study that matches those conditions, an exact conversion chart is fabricated precision.

A district may use an approved local linking study or probability model to identify students who are likely to reach a CAASPP level. If so, ask for the study name, year, grade, subject, sample, and probability threshold. “Likely Level 3” means an estimated probability, not a guaranteed future result. Families should never use an unofficial online table to override the school’s validated interpretation.

Can i-Ready predict CAASPP performance?

i-Ready can be one useful early indicator because both assessments measure important reading, language, reasoning, and mathematics knowledge. A student who consistently performs on grade level in i-Ready, demonstrates strong domain skills, and produces solid classroom work may be well positioned for the state assessment. But prediction is not certainty.

Several factors can create different results:

• i-Ready may be administered months before CAASPP.
• The two tests sample content differently.
• CAASPP includes a performance task and extended application.
• Student motivation, fatigue, attendance, and testing conditions can vary.
• Instruction between the two dates may strengthen previously weak skills.
• Each score contains measurement uncertainty.

The strongest prediction uses multiple sources: recent i-Ready performance, classroom assessments, writing samples, standards-based assignments, teacher observation, and any validated district benchmark. The purpose is to identify support early, not label a child months before the summative test.

Reading and ELA: what is different?

i-Ready Reading is designed to locate skills across a developmental progression. For younger students, it can provide detailed information about phonological awareness, phonics, and high-frequency words. Across grades it also examines vocabulary and comprehension. That detail is valuable for answering the instructional question, “Which reading skill should we work on next?”

CAASPP ELA evaluates grade-level English language arts/literacy standards at the end of the year. Students read literary and informational sources, analyze ideas and evidence, listen, research, and write. The performance task is especially important because students must integrate information and communicate a developed response. A student with adequate basic comprehension may still need practice organizing evidence, writing clearly, or sustaining attention across connected sources.

For preparation, do not replace real literacy instruction with endless multiple-choice drills. Students benefit more from daily reading, vocabulary in context, discussion of evidence, short constructed responses, revision of writing, and familiarity with the test interface. i-Ready domain data can help identify foundational gaps, while classroom work can build the extended reasoning expected on CAASPP.

Mathematics: what is different?

i-Ready Mathematics describes performance across domains such as Number and Operations, Algebra and Algebraic Thinking, Measurement and Data, and Geometry. It can reveal that the overall score is being held back by a particular area and can support instructional grouping or targeted practice.

CAASPP mathematics measures grade-level California Common Core standards and emphasizes more than calculation. Students must understand concepts, choose strategies, solve multi-step problems, model situations, interpret data, and communicate reasoning. The performance task can require students to connect several steps and explain how they know an answer is reasonable.

A child may therefore have a solid i-Ready overall score but struggle with a long CAASPP modeling task, or show strong classroom reasoning while an early i-Ready result is lowered by unfinished prerequisite skills. The response should match the evidence: practice explaining thinking and applying concepts, while also repairing specific foundational gaps found in the diagnostic report.

Growth: Typical Growth vs CAASPP progress

i-Ready’s Typical Growth and Stretch Growth are individualized targets anchored to the student’s starting performance. A dashboard may show the percentage of an annual target already achieved. This allows schools to monitor progress within one year and discuss whether a student is on pace toward an appropriate instructional goal.

CAASPP summative results are annual. Families may see score history across grades, and California uses statewide growth methods for reporting school and student-group progress. That is not the same calculation as i-Ready Typical Growth. Do not compare “80 percent of Typical Growth” with “Level 3 Proficient” as if both were percentages of the same target.

A student can meet i-Ready Typical Growth and remain below the CAASPP proficient standard because the starting point was well below grade level. A student already performing above grade level can post modest i-Ready growth and still score Advanced on CAASPP. Achievement asks where performance is now; growth asks how much it changed. A complete interpretation needs both.

For a deeper explanation of these terms, read i-Ready Typical Growth vs Stretch Growth and the guide to fall, winter, and spring i-Ready scores.

Which test matters more?

The answer depends on the decision. CAASPP is the official statewide summative measure and contributes to public reporting and California’s accountability system. If the question is, “How did this student perform on end-of-year California grade-level standards?” the CAASPP result is the direct evidence.

If the question is, “What should we teach next week, which domain needs support, or what growth target should we monitor?” i-Ready is often more immediately actionable. Its multiple administrations and detailed placement information are designed for instructional use.

Neither score should replace teacher knowledge or student work. California’s own family report describes assessment results as one measure that should be combined with other information. A strong decision combines state results, diagnostic results, grades, assignments, observation, attendance, and the student’s learning experience.

What if i-Ready and CAASPP disagree?

Disagreement is not automatically an error. First confirm that you are comparing the same subject and a reasonably close period. A fall i-Ready Math score and a late-spring CAASPP Math score are separated by most of a school year. Similarly, an i-Ready Reading placement and CAASPP ELA performance are related but not identical constructs.

Next, inspect subskill evidence. If i-Ready indicates on-grade-level reading but CAASPP ELA is Developing, look at writing/research and the student’s ability to explain evidence across longer tasks. If CAASPP Math is Proficient but i-Ready Math placement is below grade level, check whether the diagnostic was rushed, interrupted, taken unusually early, or affected by one domain.

Then ask the teacher for corroborating evidence. Recent assignments, curriculum assessments, written responses, and observations can show which result better reflects everyday performance. If neither fits, the school may examine testing records, confirm completion, or collect a fresh instructional measure. The goal is not to choose the more flattering score; it is to understand the pattern accurately.

How parents should read both reports together

1. Verify the assessment. Confirm that CAASPP means Smarter Balanced ELA or mathematics, not CAST, CAA, or CSA.
2. Match the subject. Compare i-Ready Reading with CAASPP ELA cautiously and i-Ready Mathematics with CAASPP Mathematics.
3. Write down both dates. Note how much instruction happened between the two tests.
4. Interpret each score on its own scale. Use i-Ready’s placement and CAASPP’s achievement level before comparing patterns.
5. Look below the total. Compare i-Ready domains with relevant CAASPP performance areas and classroom evidence.
6. Separate growth from achievement. A student can grow substantially without yet reaching proficiency.
7. Check engagement and conditions. Ask whether rushing, illness, fatigue, technology, or interrupted sessions may have affected performance.
8. Choose one or two priorities. Convert the evidence into a manageable practice plan rather than attempting to reteach every low area at once.
9. Set a review date. Revisit classwork or the next local assessment after several weeks.

What counts as a good score?

On CAASPP, Level 3 Proficient means the student demonstrated proficient grade-level knowledge and skills; Level 4 Advanced indicates a more sophisticated level of knowledge and application. Levels 1 and 2 signal that additional support may be appropriate, but they are not failing grades or permanent labels.

On i-Ready, “good” is more contextual. On-grade-level placement is a positive achievement indicator, but a student beginning below grade level may have an excellent year by making strong progress toward Typical or Stretch Growth. An above-grade-level student may need enrichment even when the scale score change is smaller.

The healthiest definition of a good result combines current achievement, meaningful growth, and usable next steps. Ask: Is the student meeting the expected standard? Are skills improving? What evidence supports the result? What should happen next? Those questions are more useful than chasing one universal number.

How to prepare without teaching to the test

• Maintain consistent attendance and sleep routines.
• Read varied fiction and nonfiction and discuss evidence from the text.
• Write regularly, including explanations, summaries, and source-based responses.
• Practice mathematics through concepts, models, multi-step problems, and reasoning—not only memorized procedures.
• Use official CAASPP practice and training tests to learn the interface and tools.
• Review i-Ready domains with the teacher and target genuine skill gaps.
• Teach students that adaptive questions may feel difficult and that persistence matters.
• Avoid last-minute score cramming or unofficial conversion charts.

Students do best when preparation is ordinary high-quality instruction plus calm familiarity with the test format. Practice should build transferable reading, writing, and mathematical reasoning—not create anxiety around a predicted level.

Frequently asked questions

Is i-Ready the same as CAASPP?

No. i-Ready Inform is a locally adopted instructional assessment. CAASPP is California’s statewide assessment system, and its Smarter Balanced summative tests are the state ELA and mathematics measures for Grades 3–8 and 11.

Does i-Ready replace CAASPP?

No. A California school may use i-Ready during the year, but that local assessment does not replace required statewide CAASPP testing for participating students.

Is CAASPP adaptive?

The general Smarter Balanced ELA and mathematics assessments include a computer-adaptive test plus a performance task. The performance task is a required applied component, so the full assessment is more than an adaptive question sequence.

Does CAASPP show a percentile rank?

The family Student Score Report centers on the overall scale score, achievement level, performance areas, and score history. This differs from i-Ready’s nationally normed percentile rank. Do not assume a CAASPP level can be translated into an i-Ready percentile.

What happened to “Standard Met” on CAASPP reports?

California changed the reporting labels beginning with 2025–2026 results. Level 3 is now Proficient instead of Standard Met; Level 4 is Advanced, Level 2 is Developing, and Level 1 is Minimal. California states that the cut scores and criteria did not change.

Can a student be on grade level in i-Ready and Developing on CAASPP?

Yes. The assessments differ in date, blueprint, tasks, and score uncertainty. Review domain and performance-area evidence, writing and reasoning demands, classroom work, and testing conditions before drawing a conclusion.

Does a high i-Ready score guarantee CAASPP Proficient or Advanced?

No. It may be encouraging evidence, especially when supported by classwork, but no single i-Ready number guarantees a future CAASPP level.

Can CAASPP results be used for instructional planning?

Yes, particularly when educators examine performance patterns and combine the result with interim and classroom evidence. However, because CAASPP is annual and summative, i-Ready may provide more immediate, repeated instructional detail during the year.

Should I worry if one score drops?

One change deserves investigation, not panic. Check the testing season, grade-level expectations, measurement uncertainty, engagement, and supporting work. A score history and multiple classroom measures provide a clearer view than one number alone.

Bottom line

i-Ready and CAASPP are most useful when each is allowed to do its own job. i-Ready Inform supplies repeated, instruction-focused information: scale score, placement, percentile, domains, and individualized growth targets. CAASPP’s Smarter Balanced assessment supplies California’s annual standards-based result: a separate ELA or math scale score, a four-level achievement classification, performance-area information, and statewide context.

Use i-Ready to ask what a student may need next. Use CAASPP to ask how the student demonstrated end-of-year California grade-level standards. Then combine both with classwork, teacher observation, and the student’s experience. Never force the numbers into an unsupported conversion table. Different scales can tell a coherent story without pretending they are the same ruler.

Official sources

• California Department of Education: Smarter Balanced Assessments for ELA and Mathematics
• California Department of Education: California Assessment System
• CAASPP: Current Reporting Achievement Level Descriptors
• CAASPP: Sample Student Score Reports
• CAASPP: Testing Windows and Frequently Asked Questions
• Curriculum Associates: i-Ready Inform Overview
• Curriculum Associates: i-Ready Inform Assessment-Leader Resources