AI Grammar Editor — more than a grammar checker
Fix grammar, spelling, punctuation, and clarity in one editor. Choose Basic, Thorough, or Style mode — each tuned for a different level of polish.
No credit card required · 300 free credits
Humanize AI Writing in 3 Simple Steps
Transform AI-generated content into natural, human-like text that bypasses detection
Your Text
Paste your AI-generated text here
Paste Your AI-Generated Text
Copy any content — assignments, blog posts, or AI-generated text.
Result
Check AI Score
See how much of your text is flagged as AI-written by detection systems.
Edit or review selection
Use AI to do more
Humanize & Improve selection
Transform your text to sound 100% human-written. Select any text to improve, fix the grammar, shorten, or lengthen it.
Benefits
Why writers pick this over a one-click tool
Three grammar modes
Basic catches errors. Thorough flags punctuation and style. Style rewrites for readability and flow.
Fixes more than grammar
Spelling, punctuation, fluency, redundancy, and awkward phrasing — all in one pass.
Works on any format
Essays, emails, blog posts, research papers. Up to 5,000 words per run on Ultra.
Grammar in 29 languages
Not English-only. Check grammar in Spanish, French, German, Chinese, Arabic, Hindi and more.
SupWriter vs. Other AI Humanizers
See why SupWriter consistently ranks as the most effective humanizer for avoiding AI detection, preserving tone, and optimizing readability.
| Features | SupWriter | Other Humanizers | Free Tools |
|---|---|---|---|
| Human Score | 99%+ | 85% | 90% |
| Turnitin | |||
| GPTZero | |||
| Originality.ai | |||
| Multilingual Support | 100+ Languages | English Only | 5 Languages |
| Built-in AI Detector | |||
| Plagiarism-Free Output | |||
| Meaning Preservation | High | Medium | Medium |
| Processing Speed | Fast (<25s) | Slow (2+ min) | Medium (1 min) |
| Fix Selection | |||
| Free Trial | 300 Words | 100 Words | No Trial |
| Buy Extra Credits |
Reviews
What our users say
Thousands of writers trust SupWriter every day
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.
It's so great and I love this app. Everyone should use it. It helped me pass my essay!
I really like this app. It rephrases my text so well that Turnitin doesn't pick it up. Pretty amazing.
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!
Really, the only one that passed the YouScan detector.
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.
FAQ
AI Grammar Editor — common questions
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