Botoi Readability API vs ProfText

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.

ProfText checks documents for vague language, patterns associated with AI-generated writing, and academic citation validity. Available on the web and through an API, it accepts text and offers a free tier with 30 clarity and detection rules. ProfText says free analysis runs in a browser Web Worker, so text stays on the user’s device and is not retained. The free plan allows unlimited analyses of up to 5,000 characters each, but excludes citation verification, AI rewrites, compliance checks, risk scoring, and shareable report links. Pro costs €9.99 per month and raises the analysis limit to 100,000 characters. It adds citation cross-checks against OpenAlex, rewrites with tone controls, compliance flags, risk grading, custom rules, and.txt and.docx uploads. Pro also includes CSV export, priority support, and report links that remain available for 90 days. Enterprise adds REST API access, bulk processing, SSO and team management, and dedicated support at a custom price. The site describes team workflows with roles, document versioning, comments, approvals, and analytics.