ProseScore – Client-side readability analyzer with 8 formulas

Summary: ProseScore evaluates text readability using eight formulas, plus sentiment analysis, keyword extraction, and SEO scoring, all processed locally in the browser to ensure privacy. It offers a free tier with basic scores and a Pro version unlocking full features including markdown export and analysis history.

What it does

ProseScore runs eight readability formulas—Flesch-Kincaid, Gunning Fog, SMOG, Coleman-Liau, ARI, Dale-Chall, Linsear Write, and Flesch Reading Ease—and averages them into a consensus grade. It also provides sentiment analysis, keyword extraction, SEO scoring, and extractive summarization, all executed client-side without sending data to servers.

Who it's for

It is designed for writers and developers seeking detailed readability and SEO insights with privacy, including those who want to integrate scoring into their own applications via the open-source textlens library.

Why it matters

By running entirely in-browser, ProseScore protects user text privacy while delivering comprehensive readability and SEO analysis without requiring accounts or internet connection after loading.