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Writing Assistant 2 alternatives tracked

Open-source alternatives to Grammarly

Grammarly is an AI writing assistant used for grammar and style checking, tone analysis, and generative text suggestions across browsers, desktop, and Microsoft Office. It integrates inline across web applications and works as a native keyboard on mobile. The Premium tier adds style guide enforcement and plagiarism detection for academic and professional use.

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The alternatives

languagetool

★ 14,439 Java LGPL-2.1

Style and Grammar Checker for 25+ Languages

languagetool-org/languagetool Updated 2026-05-05

vale

★ 5,368 Go MIT

:pencil: A markup-aware linter for prose built with speed and extensibility in mind.

errata-ai/vale Updated 2026-05-01

Comparison notes

LanguageTool is the OSS alternative with the broadest language coverage (25+ languages) for grammar and style checking, available as self-hosted Java server or browser extension. Vale is a prose linter for technical writers enforcing custom style rules in CI pipelines (targeting docs-as-code workflows). The main gaps vs. Grammarly: LanguageTool does not offer tone analysis, readability scoring, or Grammarly's AI generative features (GrammarlyGO). Vale targets developers writing documentation, not general prose. Neither OSS tool offers the seamless browser-native inline experience Grammarly provides across all web fields.

Migration tips

  • LanguageTool offers a browser extension that replaces Grammarly in most text fields — install and configure the server URL for self-hosted use
  • Export Grammarly personal dictionary words and add them to LanguageTool's personal word list
  • Evaluate whether LanguageTool's rule set covers your primary writing concerns — technical jargon and domain-specific rules may need custom LanguageTool rules
  • For documentation teams, Vale can enforce house style in CI — set it up in your docs build pipeline alongside your regular grammar tool
  • Grammarly's Microsoft Office integration is plugin-based — LanguageTool also offers a Word plugin as replacement

FAQ

Can I fully replace Grammarly with an OSS tool?

Feature parity varies. Most OSS alternatives cover 70-90% of core workflows, but may lack polish, integrations, or specialized features. Pilot the alternative with a subset of your team before fully committing.

What's the cost of self-hosting?

Plan for ~$5-50/month in VPS costs (DigitalOcean, Hetzner, etc.) plus 2-8 hours/month in maintenance. For a team of 20+, self-hosting usually breaks even against SaaS pricing within 6-12 months.

Which alternative should I pick?

Sort by GitHub stars (a proxy for community health), check the last-pushed date (avoid unmaintained projects), and read recent issues to gauge responsiveness.