textlint

textlint is a rule-driven natural-language checker for people who want editorial standards embedded in writing and development workflows. It is a strong fit for technical writers and engineering teams willing to assemble their own rule set; readers seeking an immediately configured grammar assistant should look elsewhere.

Overview

textlint converts text into an abstract syntax tree, runs selected rules against that structure, and reports warnings or errors. This architecture makes project-specific standards possible instead of forcing one universal style. The trade-off is deliberate setup: the software ships without bundled rules, so every useful check starts with installing and configuring the rules you choose.

The project is free, open source, and MIT-licensed, with permission to use, modify, distribute, and sublicense it under the license conditions. Node.js 20 or later is required. Documentation and community discussions provide support channels, while bugs and feature requests are directed to the project issue tracker.

Key features

Markdown and plain text are handled out of the box, covering common documentation and prose repositories. Plugins can add HTML and other formats, giving teams a path to lint content in publishing systems that need more than the defaults. Since rules are separate packages, the quality and scope of checking depend on the standards your team selects and maintains.

The command-line interface can fix problems automatically and emit results through multiple formatters. That is useful for repeatable local cleanup and for feeding lint results into scripts or review tooling, although automatic changes should be limited to rules whose corrections you trust.

Editor integrations are documented for Visual Studio Code, Vim, Emacs, Atom, Sublime Text, micro, and NetBeans. These options put the same configurable checks near the writing surface rather than leaving authors to run a separate command. In continuous integration, textlint runs in GitHub Actions and can check text changed in commits and pull requests, making style enforcement part of a team’s development process.

The CLI can also operate as an MCP server. AI assistants can then lint and fix text against the project’s textlint configuration, so generated edits follow the same rules as human-authored content. The textlint package exposes high-level APIs for applications that need programmatic linting instead of shelling out to the CLI.

For browser-based work, the integrations documentation describes @textlint/editor as a privacy-first extension that lints text offline. That is a practical option when text should stay on the device, provided the browser workflow matches the rules and formats your project uses.

Pricing

The textlint plan costs free. It is MIT-licensed software with no subscription charge, but Node.js 20 or later is required and rules must be installed separately. There are no paid tiers, seat allowances, usage quotas, or renewal terms to weigh; the cost is shifted from licensing to configuration and maintenance. It suits individuals, open-source projects, and teams that can manage dependencies themselves. Readers who want a vendor-supplied rule library or a turnkey service will need a different product.

Platforms

textlint is available through an API, editor extension integrations, Linux, macOS, the web, and Windows. The platform range supports both local development and browser editing, while the Node.js requirement remains relevant wherever the core tooling is installed.

Who it's for

Choose textlint when your organization needs enforceable, version-controlled writing rules across editors, pull requests, CI, AI-assisted editing, or an application API. It is particularly well suited to documentation teams and developers who already use Node.js and are comfortable evaluating third-party rules. It is a poor match for casual users who expect instant grammar or style suggestions without package selection, configuration, or maintenance.

Pros and cons

Pros

• Highly configurable: a pluggable rule model lets each project define its own checks.
• Workflow coverage: CLI, editor integrations, GitHub Actions, MCP, browser extension, and high-level APIs support different stages of content production.
• Automation: automatic fixes and multiple output formatters make results easier to integrate into scripts and review pipelines.
• Broad format path: Markdown and plain text work by default, with plugins available for HTML and other formats.
• No license fee: the MIT-licensed software can be used and redistributed under its stated conditions.

Cons

• No starter rules: a new installation has nothing meaningful to check until users install and configure rule packages.
• Node.js dependency: the Node.js 20+ requirement excludes environments that cannot adopt that runtime.
• Configuration responsibility: teams must choose, tune, and maintain rules rather than relying on a vendor-managed style system.

Alternatives

Writing Style Checkers is the broader category to browse when you want to compare purpose-built style tools.

DeepL Write is the better choice for a consumer-facing writing assistant with Android and iOS apps, desktop platforms, and an optional Write Pro add-on at €6.99 a month when billed annually.

Trinka suits users wanting a freemium, web-based writing product with API, extension, macOS, Windows, and self-hosted options rather than assembling rules themselves.

Vale is a close alternative for teams seeking a free, MIT-licensed, open-source style linter across Linux, macOS, Windows, web, and self-hosted deployments.

Content Checker is worth considering when an offline free app for Android, iOS, macOS, or the web is the priority.

Sapling is aimed at users who prefer a freemium service with extensions, API, web, Windows, and self-hosted support plus a free tier with stated AI-detector and snippet limits.

ProWritingAid is an extension-based freemium option with a capped free plan for writers starting out.

Revise is a freemium API, web, and self-hosted alternative.

StyleMCP is a freemium API-oriented option with a free monthly request allowance and paid plans.

Verdict

textlint is the right pick for technical writers and development teams that want open-source, programmable language checks aligned to their own rules across editors and CI. Its main reason to choose it is workflow control without licensing cost. Its main reason to look elsewhere is the setup burden: users must supply the rules and meet the Node.js 20+ requirement before the tool becomes useful.