AI Readability vs Botoi Readability API

AI Readability is a web checker for English text aimed at writers, editors, and content teams. It measures how readily people can read text and how easily AI systems can parse and reuse it. The checker returns a score from 0 to 100 covering Sentence Clarity, Structural Organization, Entity Consistency, and Answer Readiness. It also offers a short illustrative rewrite, rather than a complete edit. Scoring runs entirely in the browser, so pasted text is not sent to a server during the check. The site says the tool uses transparent heuristics without a model call, server, or crawl, and requires no signup. English is the only supported language. Selecting “Continue in Textorum” sends the text to Textorum through the URL. The maker describes the score as a proprietary diagnostic framework, not a validated scientific instrument, and says no readability tool can promise citations or rankings. The free plan costs nothing.

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.