2026 Lexile and Quantile Norms FAQ
Norms show how a student's performance compares with other students in the same grade and season. The questions below cover what norms tell you, who they are based on, and what changed in the 2026 update.
What are norms?
Norms are a way of comparing a student's performance to a large group of peers in the same grade. They help educators and parents understand how a student's reading or mathematics achievement compares with that of their peers nationwide.
What do norms tell you about a student's performance?
The norms show how a student's performance compares with that of other students in the same grade and season nationwide. They provide:
- National percentile ranks to show how a student compares with peers.
- Seasonal norms (fall, winter, and spring) to account for expected learning throughout the school year.
What do norms not tell you about a student's performance?
Norms do not indicate whether a student has met state or local proficiency standards. They compare a student's performance to a national reference group, not to state-specific achievement expectations.
Norms also do not define expected student growth. They describe how students typically perform at a given grade and testing window (fall, winter, or spring), but they do not indicate how much an individual student's Lexile® or Quantile® measure is expected to change over time.
How should norms be used?
Norms provide valuable context for understanding how a student's performance compares with peers nationwide, but they should be considered only one part of a comprehensive picture of student learning.
For educators: Use Lexile and Quantile measures alongside classroom performance, teacher observations, curriculum-based assessments, and other relevant information to understand and monitor student progress and to inform instructional decisions.
For families: National comparisons can provide helpful context, but one of the most important indicators of success is your child's individual growth over time. Consider your child's Lexile or Quantile measure alongside feedback from teachers, classroom work, and other information that reflects their ongoing learning and development.
Who are the norms based on?
The norms are based on assessment results from millions of students in kindergarten through Grade 12 who received Lexile or Quantile measures across the United States. The sample includes students from all four major U.S. regions (Midwest, Northeast, South, and West), representing all 50 states, and was collected over multiple school years (2021–2025). Data from both interim and summative assessments were included, providing a broad picture of student performance across the school year. This large, geographically diverse sample helps ensure that student scores can be compared to a broad, representative population of peers.
Are these norms nationally representative?
These norms are designed to provide a national reference for interpreting student performance. They are based on student performance from linked assessments reported across all 50 states during the study period (2021–2025). The data reflect typical operational assessment and reporting conditions and were weighted to align with the distribution of students across the four NCES regions (Midwest, Northeast, South, and West).
However, the norms are not based on a systematic national sampling plan designed to mirror the demographic, geographic, and socioeconomic characteristics of the U.S. student population. While data were collected from all 50 states, the assessments administered and student populations represented vary across states. As a result, these norms should be viewed as a national reference based on a large, geographically diverse sample rather than a statistically nationally representative sample.
Can interim and summative assessment results be combined in the same norms?
Yes. The Lexile and Quantile norms were calculated using information from both interim and summative assessments. Lexile and Quantile measures are reported on universal scales, allowing results from different assessments to be interpreted consistently regardless of the assessment from which they originated. Because the measures share a common scale, results from both interim and summative assessments can be used to develop national norms, providing a comprehensive picture of student performance throughout the school year.
Why do the norms show flat or declining growth in 11th and 12th grade?
Lexile and Quantile performance in later grades (11 and 12) does not demonstrate notable increases in the data used to calculate the norms, indicating that actual student performance is similar to prior grades or even lower. These results are similar to results observed by researchers, assessment providers, and federal education and assessment agencies (for example, NAEP).
Why were the norms updated?
Student achievement changes over time as educational standards, instructional practices, and learning opportunities evolve. Just as pediatricians periodically update children's growth charts, educational organizations periodically update assessment norms to ensure comparisons reflect the performance of today's students. Updating norms is a standard and expected part of maintaining meaningful, current reporting. Norms are typically updated every 5–7 years.
What has changed?
The comparison group has changed and now represents data from more than 37 million students collected from 2021–2025. The assessments have not changed, and a student's Lexile or Quantile measure does not change because of the updated norms. A Lexile measure continues to represent a student's reading ability, and a Quantile measure continues to represent a student's mathematics achievement using the same trusted scales educators have relied on for years.
Will my percentile rank change?
Possibly. Percentile ranks compare a student's performance to a national reference group. Because the reference group has been updated, a student's percentile rank may change even if their Lexile or Quantile measure remains exactly the same. A change in percentile rank reflects an updated comparison to today's student population, not a change in the student's reading or mathematics achievement.
What might I notice?
Because a child's results are now being compared with a more current national reference group, families and educators may notice changes in:
- Percentile rank
- Performance categories
- How a child's achievement compares with national averages
These changes reflect updates to the comparison group, not changes to the assessment or to a student's Lexile or Quantile measure.
Changes to the norms do not necessarily mean a student is performing better or worse than before. Instead, they reflect an updated comparison with the performance of today's student population. Overall, the new norms indicate lower student percentile ranks across many grade levels compared to the previous norms, a pattern that is consistent with broader trends reported by other assessment providers, although patterns vary by grade and subject. As a result, percentile ranks and other norm-referenced interpretations may differ from those based on the previous norms.
For example, if a student has a Lexile measure of 850L, that measure remains 850L. However, the percentage of students nationwide who score above or below 850L may have changed since the previous norms were established.
Will updating norms affect the Lexile and Quantile measures reported by my linked assessment?
No. Updating norms does not change a student's Lexile or Quantile measure. The measures are based on the assessment and its psychometric linking — not on the normative sample. Updated norms may change percentile ranks, national comparisons, and growth expectations, but they do not change the underlying measure.