How to use this tool
- Paste or type your text into the box above.
- Read your Flesch Reading Ease score and grade badge, updated live as you type.
- Check the three extra formulas (Gunning Fog, SMOG, Coleman-Liau) for a cross-check if the Flesch scores seem off for your text.
What Flesch Reading Ease actually measures
Flesch Reading Ease returns a score from 0 to 100, where higher means easier to read. It's built from two inputs only: average sentence length and average syllables per word. Longer sentences and longer words both pull the score down. There's no analysis of vocabulary difficulty, tone, or meaning, just structure, which is why the math runs instantly without needing a server.
| Score | Difficulty | Reading level |
|---|---|---|
| 90–100 | Very easy | 5th grade |
| 80–89 | Easy | 6th grade |
| 70–79 | Fairly easy | 7th grade |
| 60–69 | Standard, plain English | 8th–9th grade |
| 50–59 | Fairly difficult | 10th–12th grade |
| 30–49 | Difficult | College |
| 0–29 | Very difficult | College graduate |
What's a good score?
It depends entirely on what you're writing:
- Landing pages and marketing copy: 65–80. Visitors scan fast and need the point immediately.
- General blog posts and web content: 60–70. Clear and natural for a broad audience.
- Help docs and onboarding text: 65–80. Instructions should be easy to follow on the first read.
- Legal and highly technical documents: 30–50 is normal and often unavoidable given the subject matter.
For most web content, aiming for 60 to 70 hits the sweet spot. That's not dumbing writing down. Plain language reads faster, gets shared more, and survives being skimmed on a phone screen.
Flesch-Kincaid Grade Level
The same two inputs (sentence length, syllables per word) feed a second formula that outputs a U.S. school grade instead of a 0–100 score. A result of 8.0 means the text is comfortable for someone reading at an 8th grade level. Many writers find Grade Level more intuitive than Reading Ease, since "grade 8" maps to a concrete audience in a way a raw number doesn't.
The other three formulas
- Gunning Fog Index estimates the years of formal education a reader needs to understand the text on a first pass. It weighs "complex words," those with three or more syllables, more heavily than the Flesch formulas do. A Fog score of 12 corresponds to a high school senior reading level.
- SMOG Index works similarly to Gunning Fog but focuses specifically on polysyllabic words. It was originally developed for evaluating health materials, where getting the difficulty estimate right matters more than usual.
- Coleman-Liau Index skips syllable counting entirely and uses character counts instead. That makes it more consistent across text types where syllable estimation gets shaky, like text full of abbreviations or numbers.
Running all four alongside Flesch gives you a cross-check. If they broadly agree, you can trust the read. If they diverge sharply, the text likely has an unusual mix, like short sentences built from long technical words, that a single formula alone would miss.