This evaluator gives developers fine-grained vocabulary insights that help ensure texts use words that align with grade-level expectations and support growth in academic language. It:
Estimates the background knowledge a student at the target grade level is likely to have.
Identifies complex words in the text (, , , and other complex words). Evaluates overall vocabulary complexity relative to that background knowledge estimate.
This evaluator returns one of the following ratings, along with a list of complex words and reasoning for you to use to determine your best course of action. Complexity ratings are relative to the target grade level you provide.
Rating
Meaning
Slightly complex
The text uses everyday, familiar vocabulary with few academic or domain-specific terms.
Moderately complex
The text includes a mix of familiar and academic vocabulary, with some Tier 2 or Tier 3 terms that may require support.
Very complex
The text relies heavily on Tier 2 and Tier 3 vocabulary with limited contextual scaffolding.
Exceedingly complex
The text uses dense academic and domain-specific vocabulary that is likely to be inaccessible without significant support.
This evaluator is provided as Early access.
Comprehensive accuracy measures are not yet available. Validation testing is ongoing.
Accuracy has been most extensively validated on Grades 3–4. We assessed performance against an expert-annotated dataset of 580+ texts. For more information, see Accuracy.
