Writing and content

Grammarly alternatives

2 open-source projects that already do this job. Free to use - not free to run, which is what the numbers on the right are for.

The full assessment →

The projects

languagetool-org/languagetool14,772LGPL-2.1Style and grammar checker supporting 25+ languages with a web UI, server, and editor integrations.Open on GitHub theJayTea/WritingTools2,397GPL-3.0System-wide grammar assistant that provides real-time suggestions using local and cloud LLMs across OS text inputs.Open on GitHub

What you give up either way

Enterprise-grade security certifications and compliance assurances (SOC 2, BYOK, DLP)
Scale and integrations across 1M+ apps and browser ecosystems
Proprietary plagiarism detection and detector/AI-humanizer tooling
Brand trust, large user base, and enterprise support SLAs

An open-source project doing the core job proves a replacement is possible. It does not prove it matches Grammarly, and it does not prove anyone has run it for a month. How we decide.