Writing and content

LanguageTool 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/languagetoolthe vendor’s own source14,772LGPL-2.1Style and Grammar Checker for 25+ LanguagesOpen on GitHub Automattic/harper14,225Apache-2.0Rust-powered offline grammar checker focused on fast, privacy-first suggestion generation.Open on GitHub

What you give up either way

Hosted Premium features and subscription management (cloud account, billing)
Any proprietary A.I. paraphrasing models or hosted paraphraser if those are not included in the open-source repo
Built-in cloud editor features like synced Personal Dictionary / statistics unless you implement them
Managed uptime/SLA and automatic platform updates

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