# Open-source alternatives for Writing assistants

> Grammar, spelling and style checkers you can run yourself, so your text never has to leave your machine.

## Paid products
- [Open-source alternatives to Grammarly](https://repoquarry.dev/alternatives/grammarly.md): Cloud writing assistant with free and paid plans that checks grammar, spelling and style, rewrites text with AI, adjusts tone, checks plagiarism and works inside browsers and desktop apps. Text is processed on Grammarly's servers. Pricing: See pricing page.

## Top ranked projects
1. [LanguageTool](https://repoquarry.dev/projects/languagetool.md): Rule-based grammar, spelling and style checker for 25+ languages; the core and HTTP server are open source (LGPL), Premium and AI rules are not. Commercial use: Partial.
2. [Harper](https://repoquarry.dev/projects/harper.md): Fast, offline English grammar and spell checker from Automattic, written in Rust, with browser extensions, editor plugins and a language server. Commercial use: Confirmed.
3. [Vale](https://repoquarry.dev/projects/vale.md): Offline command-line prose linter that enforces a style guide (Microsoft, Google or your own rules) in your editor, in CI and on Markdown files. Commercial use: Confirmed.
4. [textlint](https://repoquarry.dev/projects/textlint.md): Pluggable Node.js linter for natural-language text, like ESLint for prose; you install rules from npm for the checks you want. Commercial use: Confirmed.
5. [Hunspell](https://repoquarry.dev/projects/hunspell.md): Widely used spell-checking library and command-line tool behind LibreOffice, Firefox and Chrome spell check, with dictionaries for many languages. Commercial use: Partial.
6. [proselint](https://repoquarry.dev/projects/proselint.md): Python command-line linter for English prose that flags usage, cliché and style problems based on advice from well-known editors and usage guides. Commercial use: Confirmed.
7. [Writing Tools](https://repoquarry.dev/projects/writing-tools.md): System-wide hotkey app that proofreads, rewrites and changes the tone of selected text using a local LLM (Ollama, MLX) or a cloud API. Commercial use: Partial.
8. [TeXtidote](https://repoquarry.dev/projects/textidote.md): Command-line spelling, grammar and style checker for LaTeX and Markdown files that maps LanguageTool results back to source lines. Commercial use: Partial.
9. [LanguageTool Integration for Obsidian](https://repoquarry.dev/projects/obsidian-languagetool.md): Obsidian plugin that underlines grammar and spelling issues using the public LanguageTool API, LanguageTool Premium or your own server. Commercial use: Partial.
10. [LTeX+](https://repoquarry.dev/projects/ltex-plus.md): Language server and VS Code extension that runs LanguageTool offline to check grammar and spelling in LaTeX, Markdown, Typst and other markup. Commercial use: Partial.
11. [Lexicon](https://repoquarry.dev/projects/lexicon.md): Local-first desktop editor with LanguageTool proofreading plus offline AI rewrite, tone and summary tools from a bundled small LLM. Commercial use: Confirmed.
12. [OmniPoly](https://repoquarry.dev/projects/omnipoly.md): Self-hosted web front end for your own LanguageTool, Harper, LibreTranslate and Ollama servers to check grammar and translate text. Commercial use: Partial.
13. [write-good](https://repoquarry.dev/projects/write-good.md): Small Node.js linter for English prose that flags passive voice, weasel words, wordy phrases and similar style issues. Commercial use: Confirmed.
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Source: RepoQuarry (https://repoquarry.dev/categories/writing-assistant). Data licence: CC BY 4.0. Quotes are from project documentation and belong to their authors.