What is an AI Grammar Checker?
An AI grammar checker reads your text and flags problems with spelling, grammar, punctuation, style, and clarity. The good ones explain why a fix matters so you write better next time. The great ones do it in any language, at any reading level, for any audience, without storing your text.
This one was built to do what the giants do not: unlimited words per check, custom style guide upload, multi-tone preview, in-browser private mode, and 30+ languages on the free tier. Privacy first. No surprise charges. One-click cancel.
How It Works
Paste your text
Drop in a sentence, paragraph, or full document. No word limit on the free tier.
Pick checks and tone
Spelling, grammar, style, clarity, inclusivity, AI-detection. Pick a target tone or reading level.
Review and apply
Inline suggestions with explanations. Accept all or pick one by one. Multi-tone preview shows 5 variants at once.
Features
Full coverage
Spelling, grammar, punctuation, style, clarity, conciseness, passive voice, weak verbs, and repetition.
Multi-tone preview
See the same paragraph rewritten in 5 tones (formal, casual, academic, persuasive, executive) in one view.
Reading level targeting
Rewrite for CEFR B1, 8th grade, executive summary, or non-native reader. Hit your audience precisely.
Inclusivity scanner
Flags gendered, ableist, or culturally biased language. Explains why so you learn for next time.
Custom style guide upload
Drop a PDF of your AP, Chicago, or company style guide. The checker enforces every rule.
In-browser ghost mode
Pro runs the check in WebAssembly. Your text never leaves your device. Built for journalists, lawyers, and doctors.
30+ languages
Spanish, French, German, Portuguese, Italian, Dutch, Russian, Polish, Korean, Hindi, and more. English variants supported.
AI-content detection per sentence
Live AI-detection score on every sentence. Find passages that read too smooth or formulaic.
Why Use This Grammar Checker?
Unlimited words on free
Most checkers cap free at 500 to 1,000 words. We give you unlimited per check, 25 checks per day.
Learn while you write
Every suggestion includes a one-sentence reason. You become a better writer just by using the tool.
Privacy-first by design
Free tier deletes your text immediately. Pro runs entirely in your browser. We never train on your work.
Honest, no dark patterns
One price, one click to cancel, email reminder before every renewal. No surprise charges, ever.
Who Is This For?
Students
Polish essays before submission. Match your professor's preferred reading level. Export with track changes for revision.
Writers and bloggers
Tighten prose, vary rhythm, catch repetition across long pieces. Style guide upload keeps brand voice consistent.
Business pros
Polish emails, reports, and proposals. Pick executive summary tone to hit your audience cleanly.
ESL writers
Native-sounding English without losing your meaning. Reading-level targeting matches your audience.
Academics
Citation-aware checking. Custom style guide for APA, MLA, Chicago. Multi-language support for European and Asian academics.
Lawyers and doctors
In-browser ghost mode means client text never leaves your device. Compliance-friendly for HIPAA and legal privilege.
Real Use Cases
- 1You finished an email at 11pm and want it polished before sending tomorrow morning.
- 2Your blog post needs to read at an 8th grade level and you have no idea where to start.
- 3Your boss asked for a formal report and you wrote it casual. You need to flip the tone in five minutes.
- 4Your essay sounds AI-generated and you need to find the robotic sentences and fix them.
- 5You wrote a proposal in Spanish and want it checked without leaving your private network.
- 6Your team has a custom style guide and you want every doc to follow it without manual review.
- 7Your cover letter has bias language you cannot see and you want a check before applying.
How Molixa Compares
How this checker stacks up against Grammarly, ProWritingAid, and LanguageTool.
| Feature | Molixa | Grammarly | ProWritingAid | LanguageTool |
|---|---|---|---|---|
| Free word limit | Unlimited | Hidden caps | 500/check | 10,000 chars |
| Languages | 30+ | 23 | 1 (6 dialects) | 30+ |
| Multi-tone preview | 5 tones at once | One at a time | No | No |
| Reading level targeting | Yes | Goal setting | Reports | No |
| Custom style guide | Yes (PDF upload) | Enterprise only | No | Pro |
| Inclusivity scanner | Yes (with reasoning) | Flags only | No | No |
| In-browser private mode | Pro | No (cloud only) | No | Self-host |
| Pricing transparency | One price, one-click cancel | Trial trap complaints | Lifetime deal | Clean |
How the Grammar Checker Works
Two-pass analysis
First pass runs a fast rule-based engine for spelling, grammar, and punctuation (the deterministic stuff). Second pass runs an AI model for style, clarity, tone, and inclusivity (the judgment calls). Both passes run together and merge into a single review.
In-browser private mode
Pro ships with a quantized language model running in WebAssembly. Your text never leaves your device. Slightly slower than cloud (1 to 2 seconds for a paragraph) but completely private. Lawyers and journalists need this.
Confidence per suggestion
Every fix has a confidence score. High-confidence suggestions get shown by default. Low-confidence ones go in an Optional tab so you are not overwhelmed by uncertain calls. Reduces the false-positive frustration that kills grammar checkers.
Frequently Asked Questions
Is the grammar checker free?
What does it check for?
Does it work in languages other than English?
Can I upload a custom style guide?
Does it integrate with Word, Google Docs, or my browser?
Is my text private?
What is the inclusivity scanner?
Can it rewrite at a target reading level?
How is this different from Grammarly?
Does it have an AI content detector built in?
Built by Molixa
Try our other writing tools, all free with no signup:
The AI Grammar Checker page is built, reviewed, and maintained by the Molixa team. We use the tool we ship and update the docs when the behavior changes.
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AI Grammar Checker vs paid alternatives
From the blog
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