Free Readability Checker — Flesch, Grade Level & Fog Index
Readable writing ranks, converts, and gets finished. This free checker scores any pasted text with the three industry-standard formulas — Flesch Reading Ease, Flesch-Kincaid Grade Level, and Gunning Fog — plus word, sentence, and syllable counts, all computed locally with transparent linguistic heuristics.
How to Score Your Writing
- Paste a representative sample — at least a paragraph; 200+ words gives stable scores.
- Click Analyze — syllables are estimated per word, sentences split on terminal punctuation, and all three formulas evaluate instantly.
- Aim for 60–70 Reading Ease (Grade 7–9) for general web content. Academic and legal writing legitimately scores lower.
What the Three Scores Mean
Flesch Reading Ease (0–100) rewards short sentences and short words: 90+ is comic-book simple, 60–70 is plain English, below 30 is academic dense. Flesch-Kincaid Grade translates the same inputs into a US school grade — Grade 8 means an eighth-grader can parse it. Gunning Fog adds a penalty for complex (3+ syllable) words, estimating years of schooling needed. Because all three derive from sentence length and word length, the fastest fix for any low score is identical: split long sentences first, then swap long words.
Why does my score differ from Word or Yoast?
Syllable counting is heuristic everywhere — no tool parses a real dictionary per word. Counts may differ by a point or two between implementations, but rankings and grade bands agree. Trends across drafts matter more than decimals.
What grade level should blog posts target?
Grade 7–9 (Reading Ease 60–70) maximizes reach: readable by teens, comfortable for graduates. News, marketing, and help docs all cluster here. Technical documentation can justify Grade 12+ when the audience is expert.
Is my text uploaded?
No. Analysis runs in page JavaScript over your pasted text; drafts never leave the browser.
Related Tools
Count the words first with the Word Counter, check originality with the Similarity Checker, and normalize style with the Case Converter.