Knip

Knip is the project linter that scans your entire JavaScript or TypeScript codebase to find unused files, exports, types, and dependencies. We rate it 92/100 — for any non-trivial JS/TS project, Knip is the single most useful maintenance tool we've added to our pipeline this year.

What is Knip?

Knip (Dutch for "to cut") is an open-source CLI built by Lars Kappert (webpro) and first released on October 4, 2022. It analyzes the entire dependency graph of a project — not just one file at a time like ESLint — and reports every export, file, type, and package that no code path actually reaches. Version 6.11.0 shipped on May 2, 2026.

The pitch is simple: less code and fewer dependencies mean smaller bundles, faster builds, fewer CVEs to patch, and easier refactors. Knip is the tool teams reach for after months of "we'll clean that up later" finally catches up to them.

Key Features of Knip

• Whole-project graph analysis: Knip walks every entry point — apps, tests, scripts, config files — and reports what nothing in the graph imports. ESLint can't do this; it only sees one file at a time.
• ~150 official plugins: Knip ships first-class understanding of Astro, Cypress, ESLint, Jest, GitHub Actions, Next.js, Nx, Remix, Storybook, Svelte, Vite, Vitest, Webpack and roughly 140 others — so framework-aware entry points are detected automatically.
• Auto-fix: The knip --fix --allow-remove-files flag deletes unused exports and files in place. Vercel used Knip to remove approximately 300,000 lines of dead code with zero reported false positives.
• VS Code extension and Language Server: Inline diagnostics surface unused symbols as you type, not just in CI.
• Monorepo and workspace support: First-class handling of pnpm, Yarn, npm, and Bun workspaces, with per-package configuration.
• MCP server: The @knip/mcp package exposes Knip's findings to AI coding agents like Claude Code and Cursor for autonomous cleanup.

What Users Say About Knip

Sentiment is unusually positive. On Reddit, Hacker News, and Bluesky, the most repeated phrase is some variation of "the best maintenance tool I've used in years." Dan Vanderkam — author of Effective TypeScript — formally retired ts-prune and updated his book's recommendation to use Knip instead. Vercel's engineering team publicly credited Knip with deleting roughly 300,000 lines of unused code from internal repositories without a single false positive.

The recurring complaints are honest: configuration for unusual setups (custom plugin systems, dynamic require calls, server-only entry points) can take an afternoon to dial in, and the first run on a large monorepo can be slow before the cache warms. Neither is a dealbreaker for most teams.

Knip Pricing

Knip is free and open source under the ISC license. There are no paid tiers, seats, or usage limits. The project is funded by GitHub Sponsors and a sponsorship banner on knip.dev, with a small Knip Pro tier for companies that want logo placement and priority issue triage.

Plan	Price	Includes
Open Source	$0	Full CLI, all ~150 plugins, VS Code extension, MCP server, language server
Sponsor (individual)	From $5/month	Same software, supports development
Sponsor (company)	From $100/month	Logo on knip.dev, priority issue triage

Who Should Use Knip?

Best for: Any team running a JavaScript or TypeScript codebase larger than a weekend project. Especially valuable for monorepos, long-lived Next.js or Remix apps, design-system packages, and codebases that have absorbed multiple framework migrations. Solo developers benefit too — running npx knip before a release routinely uncovers a forgotten dependency or an exported helper nothing imports anymore.

Not ideal for: Pure server-side projects in non-JS languages (Knip is JS/TS only), or tiny single-file scripts where there is nothing to find.

Pros and Cons

Pros:

• Catches unused dependencies, exports, types, and files in one pass — ESLint and TypeScript on their own miss most of these.
• Zero-config works on most popular setups thanks to the ~150-plugin ecosystem.
• Auto-fix mode actually deletes the dead code instead of just listing it.
• Real production track record: Vercel, Storybook, TanStack, and others publicly use it.
• Generous, friendly maintainer; releases are frequent and changelogs are detailed.

Cons:

• Edge cases (dynamic imports, Vite virtual modules, Next.js app-router server boundaries) sometimes need manual entry-point hints.
• First run on a large monorepo can take several minutes before the file cache warms.
• Auto-fix should be reviewed in a pull request — "unused" can be a code smell rather than truly dead code.

Alternatives to Knip

ts-prune is officially in maintenance mode and its README now points to Knip. depcheck only looks at unused dependencies (not exports or files). unimported is unmaintained. ESLint's no-unused-vars works file-by-file and misses everything Knip is designed to find. For practical purposes, Knip has no current peer in the JS/TS ecosystem.

Verdict: Is Knip Worth It?

Yes — emphatically. Knip is free, ships in a single npm install, runs in CI, and routinely finds real waste in real codebases. We score it 92/100. The only reason it isn't a 95+ is that fully tuning configuration for an unusual project takes some patience. For everyone else, npx knip on Monday morning is one of the highest-leverage things a JavaScript or TypeScript team can do.

Frequently Asked Questions

Is Knip free?

Yes. Knip is free and open source under the ISC license. There is no paid version of the tool itself; sponsorship plans exist only to fund development.

What platforms does Knip support?

Knip runs anywhere Node.js does — macOS, Linux, Windows, and CI environments. It supports JavaScript, TypeScript, JSX, and TSX.

How does Knip compare to ts-prune?

ts-prune was the previous standard for finding unused TypeScript exports but is now in maintenance mode. Its own author redirects users to Knip, which additionally finds unused dependencies, files, types, and class members, and ships ~150 plugins for popular frameworks.

Is Knip open source?

Yes. The source is hosted at github.com/webpro-nl/knip under the ISC license.

Can Knip auto-remove unused code?

Yes. Run knip --fix --allow-remove-files to delete unused exports and files in place. The change should still be reviewed in a pull request before merging.