Botoi Readability API vs eReadable

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.

eReadable is a free web-based writing tool for examining readability and adapting text to a target reading level. Its checker reports readability scores and grade levels, then flags difficult lines for review. The Text Simplifier rewrites dense passages in clearer English while aiming to retain required meaning. The Plain English Checker identifies jargon, legalistic wording, vague phrases, and passive voice, suggesting clearer alternatives. A Reading Level Converter supports grade and CEFR targets such as Grade 5, Grade 8, Grade 10, B1, and B2. The Sentence Rewriter offers clearer, shorter, or more direct versions for individual lines. eReadable combines formulas, structural checks, and task-specific rewriting, including Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, and SMOG. It accepts text input and includes grade-level analysis, sentence-complexity checks, and plain-language rewrites. Automated output still requires review for meaning, terminology, factual accuracy, and legal accuracy.