Fix Grammar in 3 Simple Steps
Check, correct, and humanize your text in seconds
Paste Your Text
Copy any text with grammar issues into the editor - essays, emails, articles, or any written content.
Check Grammar
Our AI scans for grammar, spelling, and punctuation errors and generates a corrected version of your text.
Get Corrected & Humanized Text
Receive corrected text that reads naturally, in your own voice, and that you can review before you submit.
Why Use SupWriter's Grammar Checker?
More than grammar correction - a complete writing improvement and humanization tool
Comprehensive Grammar Fix
Catches and fixes grammar errors, subject-verb agreement, tense issues, and sentence structure problems.
Check Before You Submit
After fixing grammar, the humanization step keeps the draft in a natural voice. The built-in AI detector adds sentence-level highlights you can review before you submit.
Multiple Check Modes
Basic mode fixes errors. Thorough mode improves structure. Style mode enhances word choice and clarity.
50+ Languages
Check grammar in 50+ languages with language-specific rules and corrections.
Instant Corrections
Get your text checked, corrected, and humanized in seconds. No waiting or complex setup.
Spelling & Punctuation
Beyond grammar - fixes spelling mistakes, punctuation errors, and commonly confused words.
Frequently Asked Questions
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.
More Grammar Tools
Explore specialized grammar and writing tools for your specific needs
Check 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.
It's so great and I love this app. Everyone should use it. It helped me pass my essay!
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.