Readability Checker
Flesch reading ease, grade level, and writing stats for any text. Free and unlimited — everything runs in a second.
Why readability matters
Books, emails, and blogs that score well get finished; dense ones get abandoned. Amazon readers decide in seconds. If your first page scores above grade 12, you are losing readers.
How to use it
Paste up to 10,000 characters and hit Check readability. You get the Flesch reading ease score, grade level, and counts for words, sentences, and syllables.
Why use this Readability Checker instead of asking ChatGPT or Claude?
Chatbots are great for ideas. This tool is for getting the job done — here's what changes when you use it instead of pasting your text into a chat app.
| Compared to a chatbot | This tool | ChatGPT / Claude |
|---|---|---|
| Speed | Instant. No prompt, no preamble, no waiting. | Type a prompt, wait for a long reply, read through it. |
| Privacy | Runs in your browser. Nothing gets uploaded or stored. | Your text is sent to and stored by a third party. |
| Format | Consistent, copy-ready output every single time. | Different style and structure every session. |
| Signup | None. Open the page and go. | Account required, limits and paid tiers involved. |
| Cost | Free. Unlimited with Tools Pro ($4.99/mo, all 18 tools). | Free tier with limits, or $20+/mo for full access. |
Use a chatbot to brainstorm. Use this tool to finish the job — then publish with Harmony when the book is ready.
Frequently asked questions
What is a good Flesch reading ease score?
60-70 reads comfortably for most adults. 80+ is very easy (children's books); 30 and below is dense academic writing. Aim for 50-70 for general readers.
What does grade level mean?
It estimates the US school grade needed to understand the text. A 9-10 grade level suits general audiences; 12+ is specialist.
Is this tool really unlimited?
Yes — readability scoring is pure math, so there is no limit and no account needed. It runs instantly in the browser.
Readability nailed?
Harmony Publishing packages include professional editing that tightens every page — you keep 100% of royalties.
See self-publishing packagesMore free tools for authors
- Word CounterCount words, characters, sentences, and reading time as you type.
- AI Text HumanizerRewrite AI-sounding text so it reads like a person wrote it.
- Book Title GeneratorGenerate ten book title ideas from your genre and theme.
- Book Description GeneratorTurn your summary into a back-cover-ready book description.
- Slug GeneratorConvert any title into a clean, SEO-friendly URL slug.