ESLint is a static code analysis tool that identifies problematic patterns in JavaScript and TypeScript code. Configuring ESLint manually can be overwhelming — there are hundreds of rules. Our ESLint Config Generator simplifies this by offering popular presets, visual rule toggles, severity controls, and instant preview of both legacy .eslintrc.json and modern flat config (eslint.config.js) formats.

Flat config (eslint.config.js) is the new configuration system introduced in ESLint v9. It replaces the legacy .eslintrc format. Key differences: flat config uses a flat array of config objects instead of nested extends; environments are replaced by globals; parsers are specified via languageOptions.parser; and plugins are imported as ES modules. Our generator outputs both formats so you can migrate at your own pace.

Migration involves: (1) Creating an eslint.config.js file; (2) Converting extends to imported config arrays; (3) Replacing env with globals from the globals npm package; (4) Moving parser and parserOptions under languageOptions; (5) Using ES module import for plugins. Use our generator's flat config tab to see the converted output instantly, then copy-paste into your project.

Start with eslint:recommended which enables rules like no-unused-vars, no-undef, no-dupe-keys, and no-unreachable. For stricter code, add eqeqeq (=== enforcement), no-var (prefer const/let), prefer-const, curly (brace consistency), and semi/quotes for formatting. Our Recommended and Standard presets bundle the most impactful rules for you.

Absolutely! Select the TypeScript preset or manually switch the parser to @typescript-eslint/parser. Our generator includes TypeScript-aware rule defaults and outputs configuration compatible with @typescript-eslint/eslint-plugin. The generated config works seamlessly with both .ts and .tsx files.

Simply copy the generated configuration and paste it into your project's .eslintrc.json or eslint.config.js file at the root directory. Then run npm install eslint --save-dev (and any required plugins/parsers). For flat config, ensure you're using ESLint v8.23+ or v9+. Use the Download button to save the file directly.

Error (2) causes ESLint to exit with code 1 — ideal for CI/CD pipelines where you want to block builds on violations. Warn (1) shows a warning but doesn't fail — great for gradual adoption or non-critical style preferences. Off (0) disables the rule entirely. Use our severity dropdowns to fine-tune each rule's behavior for your team's workflow.