Score English text readability (Flesch, Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, ARI)
score_readabilityRead-onlyIdempotent
Compute readability scores for English text: Flesch Reading Ease, Flesch-Kincaid grade, Gunning Fog, SMOG, Coleman-Liau, ARI and a consensus grade, with plain-English interpretation, text statistics (words, sentences, syllables, reading and speaking time) and the sentences longer than a threshold. Read-only; the text is scored in memory and never stored or logged. Same engine as the PlainGrade JSON API (POST /v1/score).
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| lang | No | Language code. Only English is supported: "en", "en-US", "en-GB", … | en |
| text | Yes | English text to score, up to 20,480 bytes (UTF-8). | |
| include_raw | No | Also return the full /v1/score JSON (every long sentence, unclipped) in structuredContent.raw. Larger output. | |
| long_sentence_words | No | A sentence with more words than this is listed as long (default 25). |
Output Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| raw | No | Full /v1/score response (only when include_raw is true) | |
| lang | Yes | ||
| tier | No | ||
| notes | No | ||
| stats | Yes | Counts and averages (words, sentences, syllables, reading_time_seconds, …) | |
| engine | No | ||
| scores | Yes | ||
| version | Yes | ||
| text_bytes | No | ||
| interpretation | Yes | ||
| long_sentences | Yes |