How long an essay can the grammar checker handle?

Up to 20,000 characters per check. Split longer essays into parts.

Does it check grammar while I write?

No. The check runs when you press the button.

Are the fluency and engagement scores official measures?

No. They are quick estimates from text statistics. Only the grammar score is based directly on LanguageTool's findings.

Does using a grammar checker count as using AI?

LanguageTool is a rule-and-statistics grammar engine, but schools define AI help differently. Check your course policy if you're unsure.

Grammar Checker for Essays

Updated 21 October 2026

This grammar checker for essays runs your draft through the open-source LanguageTool engine and lists spelling, grammar and style issues with suggested fixes. It handles up to 20,000 characters per check, which covers most school and college essays, and shows quick estimates for grammar, fluency, clarity and engagement.

Limitations: Suggestions come from LanguageTool and can be wrong; fluency, clarity and engagement scores are estimates. How results can be wrong →

Open the Grammar Checker →

3 free scans in total, shared across all five tools (not per day or per month). No signup needed to start.

How the Grammar Checker for Essays Works

Paste or upload: paste the essay, or upload a .docx, .pdf, .txt or .md file up to 8 MB.
Run the check: the check runs when you press the button; it doesn't run while you are still writing.
Review suggestions: each issue shows LanguageTool's explanation and suggested replacement.
Scores: Grammar, Fluency, Clarity and Engagement scores, with an overall label of Excellent, Good or Needs Work.

What the Scores Mean (and Don't)

The Grammar score comes directly from the issues LanguageTool finds. Fluency, Clarity and Engagement are our own quick estimates built from text statistics, such as how much sentence length varies, how varied your vocabulary is, and how often passive voice is flagged. They are a glance, not a grade.

A teacher's rubric will look at your argument, evidence and structure, which no grammar tool measures. Use the scores to find rough patches, then read the essay yourself.

Common Essay Issues to Look For

Run-on sentences: long sentences joined with commas; split them or use a semicolon correctly.
Agreement errors: subjects and verbs that don't match, especially after long phrases.
Wordiness: phrases like "due to the fact that" that can be cut to one word.
Passive voice: fine in moderation, but heavy use can hide who did what.

Accept Suggestions With Care

Grammar tools sometimes suggest changes that alter your meaning or flatten your voice. Accept the fixes that are clearly errors and think twice about style rewrites, especially in personal essays where your voice is the point.