Free Readability Checker
Analyze your text's readability with Flesch-Kincaid scoring. Get grade level, reading ease score, and clear interpretation.
Check Readability in 3 Simple Steps
Analyze and improve your text's readability instantly
Paste Your Text
Copy any text into the editor - blog posts, essays, emails, or marketing copy you want to analyze for readability.
Get Your Score
The tool calculates your Flesch-Kincaid reading ease score and grade level instantly using proven readability formulas.
Improve Your Writing
Use the score and interpretation to simplify complex text, shorten sentences, and make your writing more accessible.
Why Use SupWriter's Readability Checker?
Understand and improve your writing's clarity with proven readability metrics
Flesch-Kincaid Score
Get the industry-standard Flesch-Kincaid reading ease score from 0-100. Higher scores mean easier-to-read text.
Grade Level Analysis
See the U.S. school grade level required to understand your text. Aim for grade 7-8 for general audiences.
Clear Interpretation
Get a plain-English interpretation of your score: Very Easy, Easy, Standard, Difficult, or Very Difficult.
Syllable Counting
Uses intelligent syllable counting heuristics to analyze word complexity and its impact on readability.
Actionable Insights
Understand exactly how to improve your readability score with clear guidance based on your results.
Instant Analysis
Get results in real-time as you type. No server requests, no waiting, no sign-up required.
Frequently Asked Questions
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Try it freeAI Humanizer
Rewrite an AI-assisted draft so it reads naturally in your own voice.
Try it freeCheck a draft before you submit
Detectors such as GPTZero, Turnitin, and ZeroGPT estimate whether a draft looks AI-written. They can also flag human writing.
SupWriter includes an AI detector so you can check a draft before you submit. It is a pre-check based on one scoring model, not the detector your school or client uses. Results vary by detector, text length and topic, and no tool can guarantee a result. How we test AI detectors
Use the built-in AI detector (free on paid plans) to review a draft before you submit. A score is an estimate, not a guarantee.
Reviews
What our users say
What writers say about SupWriter
I've been using SupWriter for weeks, and it's become essential to my academic writing and research workflow. As a Ph.D. student in environmental law, I'm constantly drafting, refining, and translating complex texts, and SupWriter makes the whole process far more efficient and less stressful.
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What impressed me most is how seamlessly SupWriter polishes my drafts. My clients noticed the difference in quality and tone immediately.
Absolutely wonderful. The best AI humanizer I've used, especially for scientific writing.
This tool lets me do so many things faster, and its features are genuinely useful.
Really good. I didn't expect it to be this great. It genuinely enhanced my writing. Give it a try.
This product is so good. I'll choose it over and over again. It has my heart. ❤️
The Fix Selection feature is a game changer. I can select any text and improve it, fix the grammar, or make it shorter, and my content workflow has never been faster.
Excellent service, really helpful for job applications, and it even has an AI detector. I'd highly recommend it to students, professors, and writers. An amazing writing tool.
It was amazing. I upgraded, and since then my work has consistently scored high marks.
The best humanizer ever.
It was great, especially in a foreign language. It helped the adjectives come out smoother than I expected!
I'm on the Ultra Monthly plan and bought $20 in extra credits. This platform is super good, and I'm planning to switch to the Yearly plan soon.
Precisely written and a very nice app. I recommend everyone give it a try.
I was amazed to see the AI-flagged text identified so accurately. It really helps crack down on AI interventions.
My professor commended the uniqueness of my essay after I used SupWriter to make it sound natural. Strongly recommended for students!
The website is fantastic. It's clean, modern, and visually appealing. Navigation is intuitive, pages load fast, and everything works well on desktop and mobile. A smooth, enjoyable experience. I'm really impressed!
It's been a great tool to use, and very helpful.
My experience with the AI detector was great. The interface is simple and easy to navigate, and results came back quickly with useful detail.
This experience has been amazing, and the service is extremely helpful.
My experience was amazing. SupWriter is very easy to use, and it actually works!
Impressed by the quality, and cheaper than other platforms.
SupWriter is great. It helps me become a better writer and a better student overall.