ESLint
The JavaScript and TypeScript linter every project ends up using.
What it is
ESLint parses JavaScript and TypeScript into an AST and applies configurable rules, with autofix for many of them. Its plugin ecosystem covers React, accessibility (jsx-a11y), imports, security patterns and framework-specific conventions, making it the enforcement point for most front-end code standards.
Best for
Where it is strong
- The plugin ecosystem lets you enforce almost any convention as a rule.
- Autofix handles a large share of findings without human effort.
- Universal — every JavaScript tool integrates with it.
Where it falls short
- Configuration is a real project of its own, and the flat-config migration caused significant churn.
- Slow on large codebases without caching.
- Rule sprawl produces bikeshedding unless someone owns the config.
Pricing
Free and open source
Open sourceFree tier: Everything, self-hosted
What drives the bill: Free and open source. You pay in engineering time and CI minutes.
Check current pricing on OpenJS Foundation’s siteFigures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.
Works with
What people who use ESLint say
No reviews of ESLint yet. If you have used it in anger, yours would be the first.
Alternatives to ESLint
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