ApyHub Readability Scores Documents API vs Eclipse Readability Studio

ApyHub Readability Scores Documents API scores documents and publicly accessible web pages, returning a readability score, reading level, and text statistics. File requests accept PDF, DOC, or DOCX uploads up to 100 MB. English checks use the Flesch Reading Ease formula by default, while German uses the Wiener Sachtextformel. Results can include word, sentence, character, and paragraph counts, average lengths, and estimated reading and speaking times. The score includes a grade class, a plain-language label, and an indication of whether a standard readability threshold is met. ApyHub lists uses such as reviewing contracts, policies, manuals, help pages, websites, reports, and proposals; AI agents can also access the API through ApyHub MCP for content reviews. The product page offers five API calls a day free without a card. Starter is free and includes 3,000 atoms per month; Pro costs $16 a month and Pro+ $42 a month. Requests can return a 429 rate_limited error when the plan's per-second limit is exceeded.

Eclipse Readability Studio analyzes documents, reports their reading levels, explains readability test results and recommends ways to improve text. It includes grammar checking and offers more than 60 readability tests in English, Spanish and German. Users can analyze a single document or process batches. Supported formats include MS Word, OpenDocument, RTF, HTML, PostScript and text files. The software is free and open source, with versions for Linux, macOS and Windows. The Eclipse project lists its status as Incubating and its license as Eclipse Public License 2.0, while noting that some source code and binaries may have different terms. The project proposal says Readability Studio has provided readability formula and grammar analysis since 2006, and names Blake Madden as project lead and copyright holder. Stated use cases include education, military and government, healthcare, publishing and students. No integrations are stated on the product or project pages.