Botoi Readability API vs Readability

Botoi Readability API analyzes English text and returns Flesch-Kincaid Grade, Flesch Reading Ease, Gunning Fog, and underlying counts. A request sends a required text string to POST /v1/text/readability and receives JSON. Flesch Reading Ease scores run from 0 to 100, with higher values indicating easier reading; Gunning Fog estimates the years of formal education needed. The formulas and syllable heuristics are calibrated for English, so grade mapping is not meaningful for other languages. Botoi recommends sending at least 100 words because short samples can produce unstable scores. Suggested uses include enforcing plain-language standards, reviewing legal or medical drafts, refining blog posts for SEO, and comparing writing across authors. Examples are provided in cURL, JavaScript, TypeScript, Python, and Go. The Free plan is free and lists 1,000 requests per day and 10 per minute; the endpoint page separately states five requests per minute for its free tier. Starter costs $9 a month. Requests above a per-minute or daily cap receive HTTP 429, and daily limits reset at midnight UTC.

Readability analyzes Markdown files and reports measures of reading complexity. It provides grade level, reading ease and estimated reading time calculated at 200 words per minute. The listed grade-level formulas are Flesch-Kincaid, Gunning Fog, Coleman-Liau, SMOG and ARI. It also measures word and sentence metrics and can detect or require MkDocs-style admonitions. Results can be produced as a table, Markdown, JSON, summary or report. Configurable thresholds can fail CI checks when documentation exceeds them, and a.readability.yml file supports path-specific overrides. The project documents a Go command-line tool, Docker, a GitHub Action and pre-commit hooks, alongside CI/CD examples for GitLab CI, CircleCI and Jenkins. Pre-built binaries are listed for Linux and macOS in amd64 and arm64, and Windows in amd64. The project identifies its license as MIT and lists no paid plans. Its documentation cautions that scores measure word and sentence complexity, not accuracy, completeness, context or tone.