How to fix Unknown compiler option 'X' in TypeScript

Check the error message to see which option TypeScript doesn't recognize:

error TS5023: Unknown compiler option 'verbatimModuleSyntax'.

The option name is shown in single quotes. Make note of it for the next steps.

Verify which TypeScript version you're using:

npx tsc --version

Also check your package.json to see the installed version:

npm list typescript

If you see a version mismatch (global vs. local), always use the project-local version for consistency.

Ensure the option is in the correct location. Some options belong at the root level, not inside compilerOptions:

Root-level options (NOT in compilerOptions):

{
  "include": ["src/**/*"],
  "exclude": ["node_modules"],
  "files": ["index.ts"],
  "extends": "./base.json",
  "references": [{ "path": "./other-project" }],
  "compilerOptions": {
    // Compiler options go here
  }
}

Compiler options (inside compilerOptions):

{
  "compilerOptions": {
    "target": "ES2020",
    "module": "commonjs",
    "strict": true,
    "verbatimModuleSyntax": true
  }
}

Move any misplaced options to their correct location.

Visit the official TSConfig Reference to check if the option exists and what version introduced it:

https://www.typescriptlang.org/tsconfig/

Search for your option and check the "Recommended" or version information. For example:
- verbatimModuleSyntax requires TypeScript 5.0+
- ignoreDeprecations requires TypeScript 5.0+
- noImplicitOverride requires TypeScript 4.3+

If the option requires a newer version than you have installed, proceed to the next step.

If the option requires a newer TypeScript version, update your project:

npm install typescript@latest --save-dev

For a specific version:

npm install [email protected] --save-dev

After updating, verify the installation:

npx tsc --version

Then try compiling again:

npx tsc

If you cannot update TypeScript (e.g., due to project constraints), remove the unsupported option or use an alternative:

{
  "compilerOptions": {
    // Remove this if TypeScript version is too old
    // "verbatimModuleSyntax": true

    // Use older alternatives instead
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true
  }
}

Check the TypeScript release notes to find equivalent settings for older versions.

If none of the above applies, double-check for typos:

Common typos:
- "targit" → "target"
- "moduel" → "module"
- "stict" → "strict"

Use your IDE's autocomplete when editing tsconfig.json. Most editors provide TypeScript schema validation and will highlight invalid options.

You can also validate your tsconfig.json using:

npx tsc --showConfig

This displays the resolved configuration and will error on unknown options.