Grammar & Spelling Fixer

How It Works

The tool runs on a modern large language model (Llama 3.3 70B via Groq by default, with Gemini and OpenRouter fallbacks). When you paste text, the model analyzes it at three levels:

1. **Mechanical** — spelling, punctuation, capitalization, formatting. 2. **Grammatical** — subject-verb agreement, pronoun agreement, tense consistency, dangling modifiers, comma splices, and other structural issues. 3. **Stylistic** — unnecessary repetition, passive voice where active would be clearer, awkward phrasing, and wordiness.

The system prompt is tuned to preserve voice: it fixes what's wrong without rewriting what's already correct. If a sentence is stylistically informal but grammatically fine, it stays. The tool also scores the original text so you get a signal about overall quality, not just individual errors.

Who Is This Tool For?

• Students — Check essays, research papers, and applications before submission. The explanation format doubles as a learning tool.
• Professionals — Proofread emails, reports, presentations, and client-facing documents in seconds.
• Non-native English speakers — Catch systematic grammar issues and see exactly why each correction was made.
• Content writers & marketers — Polish copy before publishing without paying for a premium grammar subscription.
• Bloggers — Run posts through this tool as a last check before hitting publish.
• Anyone sending important messages — Job applications, cover letters, proposals — anything where a single error hurts credibility.

How to Use the Grammar & Spelling Fixer

1. Paste your text into the input box. Up to ~800 words per request works well; for longer documents, do it in sections.
2. Click ✨ Generate. The tool analyzes the text, produces the corrected version, and lists every change.
3. Read the corrected version — it's ready to copy as-is if you don't want to learn from the changes.
4. Read the 'Changes Made' list. This is where the real value is: each entry tells you what was wrong and why.
5. Copy the corrected text back into your document or email.
6. If you notice the same mistake appearing in multiple drafts, note the pattern — that's the fastest way to actually improve your writing over time.

Real Examples

Their going to the store becuse they need to by some grocerys. Me and him was talking about it yesterday and we decied to went together.

✅ CORRECTED TEXT:
    They're going to the store because they need to buy some groceries. He and I were talking about it yesterday and we decided to go together.

    📝 CHANGES MADE:
    - Changed "Their" → "They're" — "Their" is possessive; "They're" is the contraction of "they are."
    - Changed "becuse" → "because" — spelling.
    - Changed "to by" → "to buy" — "by" is a preposition; "buy" is the verb.
    - Changed "grocerys" → "groceries" — plural spelling of "grocery."
    - Changed "Me and him was" → "He and I were" — subject pronouns and correct verb agreement.
    - Changed "decied" → "decided" — spelling.
    - Changed "to went" → "to go" — after "to," use the base form of the verb.

    Score: 2/10 — numerous basic errors throughout; needs a full rewrite for professional use.

The team have been working on this project since three months and they has made significant progress. Each of the members were assigned specific tasks, and everyone have completed their part.

✅ CORRECTED TEXT:
    The team has been working on this project for three months and has made significant progress. Each of the members was assigned specific tasks, and everyone has completed their part.

    📝 CHANGES MADE:
    - Changed "have" → "has" — "team" is a collective noun and takes a singular verb in American English.
    - Changed "since three months" → "for three months" — "since" is used with a specific point in time; "for" is used with a duration.
    - Changed "they has" → "has" — subject-verb agreement with the collective noun.
    - Changed "were" → "was" — "each" is singular.
    - Changed "have" → "has" — "everyone" is singular.

    Score: 6/10 — meaning is clear, but several agreement and preposition errors affect polish.

We need to finalize the report by friday however the data from marketing isnt ready yet. Can you follow up with them, and let me know by tommorow

✅ CORRECTED TEXT:
    We need to finalize the report by Friday; however, the data from marketing isn't ready yet. Can you follow up with them and let me know by tomorrow?

    📝 CHANGES MADE:
    - Changed "friday" → "Friday" — days of the week are capitalized.
    - Added semicolon before "however" and comma after — "however" as a conjunctive adverb needs this punctuation.
    - Changed "isnt" → "isn't" — missing apostrophe in contraction.
    - Removed comma before "and" — not needed between two verb phrases in a compound predicate.
    - Added question mark at the end — the sentence is a question.
    - Changed "tommorow" → "tomorrow" — spelling.

    Score: 5/10 — clear intent, but punctuation and spelling errors distract from the message.

Technical Details

Powered by Llama 3.3 70B (Groq primary, with Gemini 1.5 Flash and OpenRouter as fallbacks). Temperature is set low — around 0.2 — because grammar correction should be deterministic, not creative. Max output: 2,048 tokens.

Notably, the tool does not "rewrite" correct sentences. This is intentional and hard-coded into the system prompt: any correct sentence must be returned unchanged. The purpose is to fix errors, not impose a style. That means the output preserves the author's voice even when the author's voice is informal or idiosyncratic.

Rate-limited to 10 requests per minute per IP. Text is not stored.

Frequently Asked Questions

Why Use MintAI Tools for This?

Most free grammar checkers only catch the obvious stuff — typos and basic punctuation — and the ones that actually work well cost $12–$30 per month. This tool catches mechanical, grammatical, and stylistic issues at once, explains every correction, and never charges. It's the tool I run every MintAI Tools blog post through before publishing.