ESLint

Name: ESLint
Author: OpenJS Foundation

The JavaScript and TypeScript linter every project ends up using.

Code QualityOpen sourceSelf-hostable

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

Every JavaScript and TypeScript project.

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 source

Free 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 site

Figures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.

Works with

VS CodePrettierGitHub ActionsSonarQubeNext.jsTypeScript

What people who use ESLint say

No reviews of ESLint yet. If you have used it in anger, yours would be the first.

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Rust-based linter and formatter that replaces ESLint and Prettier, very fast.

Open sourceSelf-host

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