TypeScript: Documentation - tsc CLI Options

Using the CLI

Running tsc locally will compile the closest project defined by a tsconfig.json, or you can compile a set of TypeScript files by passing in a glob of files you want. When input files are specified on the command line, tsconfig.json files are ignored.

sh
# Run a compile based on a backwards look through the fs for a tsconfig.json
tsc
# Emit JS for just the index.ts with the compiler defaults
tsc index.ts
# Emit JS for any .ts files in the folder src, with the default settings
tsc src/*.ts
# Emit files referenced in with the compiler settings from tsconfig.production.json
tsc --project tsconfig.production.json
# Emit d.ts files for a js file with showing compiler options which are booleans
tsc index.js --declaration --emitDeclarationOnly
# Emit a single .js file from two files via compiler options which take string arguments
tsc app.ts util.ts --target esnext --outfile index.js

Compiler Options

If you’re looking for more information about the compiler options in a tsconfig, check out the TSConfig Reference

CLI Commands

Flag	Type
`--all`	`boolean`
Show all compiler options.
`--help`	`boolean`
Gives local information for help on the CLI.
`--init`	`boolean`
Initializes a TypeScript project and creates a tsconfig.json file.
`--listFilesOnly`	`boolean`
Print names of files that are part of the compilation and then stop processing.
`--locale`	`string`
Set the language of the messaging from TypeScript. This does not affect emit.
`--project`	`string`
Compile the project given the path to its configuration file, or to a folder with a 'tsconfig.json'.
`--showConfig`	`boolean`
Print the final configuration instead of building.
`--version`	`boolean`
Print the compiler's version.

Build Options

Flag	Type
`--build`	`boolean`
Build one or more projects and their dependencies, if out of date
`--clean`	`boolean`
Delete the outputs of all projects.
`--dry`	`boolean`
Show what would be built (or deleted, if specified with '--clean')
`--force`	`boolean`
Build all projects, including those that appear to be up to date.
`--verbose`	`boolean`
Enable verbose logging.

Watch Options

Flag	Type
`--excludeDirectories`	`list`
Remove a list of directories from the watch process.
`--excludeFiles`	`list`
Remove a list of files from the watch mode's processing.
`--fallbackPolling`	`fixedinterval`, `priorityinterval`, `dynamicpriority`, or `fixedchunksize`
Specify what approach the watcher should use if the system runs out of native file watchers.
`--synchronousWatchDirectory`	`boolean`
Synchronously call callbacks and update the state of directory watchers on platforms that don`t support recursive watching natively.
`--watch`	`boolean`
Watch input files.
`--watchDirectory`	`usefsevents`, `fixedpollinginterval`, `dynamicprioritypolling`, or `fixedchunksizepolling`
Specify how directories are watched on systems that lack recursive file-watching functionality.
`--watchFile`	`fixedpollinginterval`, `prioritypollinginterval`, `dynamicprioritypolling`, `fixedchunksizepolling`, `usefsevents`, or `usefseventsonparentdirectory`
Specify how the TypeScript watch mode works.

Compiler Flags

Flag	Type	Default
`--allowArbitraryExtensions`	`boolean`	`false`
Enable importing files with any extension, provided a declaration file is present.
`--allowImportingTsExtensions`	`boolean`	`true` if `rewriteRelativeImportExtensions`; `false` otherwise.
Allow imports to include TypeScript file extensions.
`--allowJs`	`boolean`	`false`
Allow JavaScript files to be a part of your program. Use the `checkJS` option to get errors from these files.
`--allowSyntheticDefaultImports`	`boolean`	`true` if `esModuleInterop` is enabled, `module` is `system`, or `moduleResolution` is `bundler`; `false` otherwise.
Allow 'import x from y' when a module doesn't have a default export.
`--allowUmdGlobalAccess`	`boolean`	`false`
Allow accessing UMD globals from modules.
`--allowUnreachableCode`	`boolean`
Disable error reporting for unreachable code.
`--allowUnusedLabels`	`boolean`
Disable error reporting for unused labels.
`--alwaysStrict`	`boolean`	`true` if `strict`; `false` otherwise.
Ensure 'use strict' is always emitted.
`--assumeChangesOnlyAffectDirectDependencies`	`boolean`	`false`
Have recompiles in projects that use `incremental` and `watch` mode assume that changes within a file will only affect files directly depending on it.
`--baseUrl`	`string`
Specify the base directory to resolve bare specifier module names.
`--charset`	`string`	`utf8`
No longer supported. In early versions, manually set the text encoding for reading files.
`--checkJs`	`boolean`	`false`
Enable error reporting in type-checked JavaScript files.
`--composite`	`boolean`	`false`
Enable constraints that allow a TypeScript project to be used with project references.
`--customConditions`	`list`
Conditions to set in addition to the resolver-specific defaults when resolving imports.
`--declaration`	`boolean`	`true` if `composite`; `false` otherwise.
Generate .d.ts files from TypeScript and JavaScript files in your project.
`--declarationDir`	`string`
Specify the output directory for generated declaration files.
`--declarationMap`	`boolean`	`false`
Create sourcemaps for d.ts files.
`--diagnostics`	`boolean`	`false`
Output compiler performance information after building.
`--disableReferencedProjectLoad`	`boolean`	`false`
Reduce the number of projects loaded automatically by TypeScript.
`--disableSizeLimit`	`boolean`	`false`
Remove the 20mb cap on total source code size for JavaScript files in the TypeScript language server.
`--disableSolutionSearching`	`boolean`	`false`
Opt a project out of multi-project reference checking when editing.
`--disableSourceOfProjectReferenceRedirect`	`boolean`	`false`
Disable preferring source files instead of declaration files when referencing composite projects.
`--downlevelIteration`	`boolean`	`false`
Emit more compliant, but verbose and less performant JavaScript for iteration.
`--emitBOM`	`boolean`	`false`
Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files.
`--emitDeclarationOnly`	`boolean`	`false`
Only output d.ts files and not JavaScript files.
`--emitDecoratorMetadata`	`boolean`	`false`
Emit design-type metadata for decorated declarations in source files.
`--erasableSyntaxOnly`	`boolean`	`false`
Do not allow runtime constructs that are not part of ECMAScript.
`--esModuleInterop`	`boolean`	`true` if `module` is `node16`, `nodenext`, or `preserve`; `false` otherwise.
Emit additional JavaScript to ease support for importing CommonJS modules. This enables `allowSyntheticDefaultImports` for type compatibility.
`--exactOptionalPropertyTypes`	`boolean`	`false`
Interpret optional property types as written, rather than adding `undefined`.
`--experimentalDecorators`	`boolean`	`false`
Enable experimental support for TC39 stage 2 draft decorators.
`--explainFiles`	`boolean`	`false`
Print files read during the compilation including why it was included.
`--extendedDiagnostics`	`boolean`	`false`
Output more detailed compiler performance information after building.
`--forceConsistentCasingInFileNames`	`boolean`	`true`
Ensure that casing is correct in imports.
`--generateCpuProfile`	`string`	`profile.cpuprofile`
Emit a v8 CPU profile of the compiler run for debugging.
`--generateTrace`	`string`
Generates an event trace and a list of types.
`--importHelpers`	`boolean`	`false`
Allow importing helper functions from tslib once per project, instead of including them per-file.
`--importsNotUsedAsValues`	`remove`, `preserve`, or `error`	`remove`
Specify emit/checking behavior for imports that are only used for types.
`--incremental`	`boolean`	`true` if `composite`; `false` otherwise.
Save .tsbuildinfo files to allow for incremental compilation of projects.
`--inlineSourceMap`	`boolean`	`false`
Include sourcemap files inside the emitted JavaScript.
`--inlineSources`	`boolean`	`false`
Include source code in the sourcemaps inside the emitted JavaScript.
`--isolatedDeclarations`	`boolean`	`false`
Require sufficient annotation on exports so other tools can trivially generate declaration files.
`--isolatedModules`	`boolean`	`true` if `verbatimModuleSyntax`; `false` otherwise.
Ensure that each file can be safely transpiled without relying on other imports.
`--jsx`	`preserve`, `react`, `react-native`, `react-jsx`, or `react-jsxdev`
Specify what JSX code is generated.
`--jsxFactory`	`string`	`React.createElement`
Specify the JSX factory function used when targeting React JSX emit, e.g. 'React.createElement' or 'h'.
`--jsxFragmentFactory`	`string`	`React.Fragment`
Specify the JSX Fragment reference used for fragments when targeting React JSX emit e.g. 'React.Fragment' or 'Fragment'.
`--jsxImportSource`	`string`	`react`
Specify module specifier used to import the JSX factory functions when using `jsx: react-jsx*`.
`--keyofStringsOnly`	`boolean`	`false`
Make keyof only return strings instead of string, numbers or symbols. Legacy option.
`--lib`	`list`
Specify a set of bundled library declaration files that describe the target runtime environment.
`--libReplacement`	`boolean`	`true`
Enable substitution of default `lib` files with custom ones.
`--listEmittedFiles`	`boolean`	`false`
Print the names of emitted files after a compilation.
`--listFiles`	`boolean`	`false`
Print all of the files read during the compilation.
`--mapRoot`	`string`
Specify the location where debugger should locate map files instead of generated locations.
`--maxNodeModuleJsDepth`	`number`	`0`
Specify the maximum folder depth used for checking JavaScript files from `node_modules`. Only applicable with `allowJs`.
`--module`	`none`, `commonjs`, `amd`, `umd`, `system`, `es6`/`es2015`, `es2020`, `es2022`, `esnext`, `node16`, `node18`, `nodenext`, or `preserve`	`CommonJS` if `target` is `ES5`; `ES6`/`ES2015` otherwise.
Specify what module code is generated.
`--moduleDetection`	`legacy`, `auto`, or `force`	"auto": Treat files with imports, exports, import.meta, jsx (with jsx: react-jsx), or esm format (with module: node16+) as modules.
Specify what method is used to detect whether a file is a script or a module.
`--moduleResolution`	`classic`, `node10`/`node`, `node16`, `nodenext`, or `bundler`	`Node10` if `module` is `CommonJS`; `Node16` if `module` is `Node16` or `Node18`; `NodeNext` if `module` is `NodeNext`; `Bundler` if `module` is `Preserve`; `Classic` otherwise.
Specify how TypeScript looks up a file from a given module specifier.
`--moduleSuffixes`	`list`
List of file name suffixes to search when resolving a module.
`--newLine`	`crlf` or `lf`	`lf`
Set the newline character for emitting files.
`--noCheck`	`boolean`	`false`
Disable full type checking (only critical parse and emit errors will be reported).
`--noEmit`	`boolean`	`false`
Disable emitting files from a compilation.
`--noEmitHelpers`	`boolean`	`false`
Disable generating custom helper functions like `__extends` in compiled output.
`--noEmitOnError`	`boolean`	`false`
Disable emitting files if any type checking errors are reported.
`--noErrorTruncation`	`boolean`	`false`
Disable truncating types in error messages.
`--noFallthroughCasesInSwitch`	`boolean`	`false`
Enable error reporting for fallthrough cases in switch statements.
`--noImplicitAny`	`boolean`	`true` if `strict`; `false` otherwise.
Enable error reporting for expressions and declarations with an implied `any` type.
`--noImplicitOverride`	`boolean`	`false`
Ensure overriding members in derived classes are marked with an override modifier.
`--noImplicitReturns`	`boolean`	`false`
Enable error reporting for codepaths that do not explicitly return in a function.
`--noImplicitThis`	`boolean`	`true` if `strict`; `false` otherwise.
Enable error reporting when `this` is given the type `any`.
`--noImplicitUseStrict`	`boolean`	`false`
Disable adding 'use strict' directives in emitted JavaScript files.
`--noLib`	`boolean`	`false`
Disable including any library files, including the default lib.d.ts.
`--noPropertyAccessFromIndexSignature`	`boolean`	`false`
Enforces using indexed accessors for keys declared using an indexed type.
`--noResolve`	`boolean`	`false`
Disallow `import`s, `require`s or `<reference>`s from expanding the number of files TypeScript should add to a project.
`--noStrictGenericChecks`	`boolean`	`false`
Disable strict checking of generic signatures in function types.
`--noUncheckedIndexedAccess`	`boolean`	`false`
Add `undefined` to a type when accessed using an index.
`--noUncheckedSideEffectImports`	`boolean`	`false`
Check side effect imports.
`--noUnusedLocals`	`boolean`	`false`
Enable error reporting when local variables aren't read.
`--noUnusedParameters`	`boolean`	`false`
Raise an error when a function parameter isn't read.
`--out`	`string`
Deprecated setting. Use `outFile` instead.
`--outDir`	`string`
Specify an output folder for all emitted files.
`--outFile`	`string`
Specify a file that bundles all outputs into one JavaScript file. If `declaration` is true, also designates a file that bundles all .d.ts output.
`--paths`	`object`
Specify a set of entries that re-map imports to additional lookup locations.
`--plugins`	`list`
Specify a list of language service plugins to include.
`--preserveConstEnums`	`boolean`	`true` if `isolatedModules`; `false` otherwise.
Disable erasing `const enum` declarations in generated code.
`--preserveSymlinks`	`boolean`	`false`
Disable resolving symlinks to their realpath. This correlates to the same flag in node.
`--preserveValueImports`	`boolean`	`false`
Preserve unused imported values in the JavaScript output that would otherwise be removed.
`--preserveWatchOutput`	`boolean`	`false`
Disable wiping the console in watch mode.
`--pretty`	`boolean`	`true`
Enable color and formatting in TypeScript's output to make compiler errors easier to read.
`--reactNamespace`	`string`	`React`
Specify the object invoked for `createElement`. This only applies when targeting `react` JSX emit.
`--removeComments`	`boolean`	`false`
Disable emitting comments.
`--resolveJsonModule`	`boolean`	`false`
Enable importing .json files.
`--resolvePackageJsonExports`	`boolean`	`true` when `moduleResolution` is `node16`, `nodenext`, or `bundler`; otherwise `false`
Use the package.json 'exports' field when resolving package imports.
`--resolvePackageJsonImports`	`boolean`	`true` when `moduleResolution` is `node16`, `nodenext`, or `bundler`; otherwise `false`
Use the package.json 'imports' field when resolving imports.
`--rewriteRelativeImportExtensions`	`boolean`	`false`
Rewrite `.ts`, `.tsx`, `.mts`, and `.cts` file extensions in relative import paths to their JavaScript equivalent in output files.
`--rootDir`	`string`	Computed from the list of input files.
Specify the root folder within your source files.
`--rootDirs`	`list`	Computed from the list of input files.
Allow multiple folders to be treated as one when resolving modules.
`--skipDefaultLibCheck`	`boolean`	`false`
Skip type checking .d.ts files that are included with TypeScript.
`--skipLibCheck`	`boolean`	`false`
Skip type checking all .d.ts files.
`--sourceMap`	`boolean`	`false`
Create source map files for emitted JavaScript files.
`--sourceRoot`	`string`
Specify the root path for debuggers to find the reference source code.
`--stopBuildOnErrors`	`boolean`
Skip building downstream projects on error in upstream project.
`--strict`	`boolean`	`false`
Enable all strict type-checking options.
`--strictBindCallApply`	`boolean`	`true` if `strict`; `false` otherwise.
Check that the arguments for `bind`, `call`, and `apply` methods match the original function.
`--strictBuiltinIteratorReturn`	`boolean`	`true` if `strict`; `false` otherwise.
Built-in iterators are instantiated with a TReturn type of undefined instead of any.
`--strictFunctionTypes`	`boolean`	`true` if `strict`; `false` otherwise.
When assigning functions, check to ensure parameters and the return values are subtype-compatible.
`--strictNullChecks`	`boolean`	`true` if `strict`; `false` otherwise.
When type checking, take into account `null` and `undefined`.
`--strictPropertyInitialization`	`boolean`	`true` if `strict`; `false` otherwise.
Check for class properties that are declared but not set in the constructor.
`--stripInternal`	`boolean`	`false`
Disable emitting declarations that have `@internal` in their JSDoc comments.
`--suppressExcessPropertyErrors`	`boolean`	`false`
Disable reporting of excess property errors during the creation of object literals.
`--suppressImplicitAnyIndexErrors`	`boolean`	`false`
Suppress `noImplicitAny` errors when indexing objects that lack index signatures.
`--target`	`es3`, `es5`, `es6`/`es2015`, `es2016`, `es2017`, `es2018`, `es2019`, `es2020`, `es2021`, `es2022`, `es2023`, `es2024`, or `esnext`	`ES5`
Set the JavaScript language version for emitted JavaScript and include compatible library declarations.
`--traceResolution`	`boolean`	`false`
Log paths used during the `moduleResolution` process.
`--tsBuildInfoFile`	`string`	`.tsbuildinfo`
The file to store `.tsbuildinfo` incremental build information in.
`--typeRoots`	`list`
Specify multiple folders that act like `./node_modules/@types`.
`--types`	`list`
Specify type package names to be included without being referenced in a source file.
`--useDefineForClassFields`	`boolean`	`true` if `target` is `ES2022` or higher, including `ESNext`; `false` otherwise.
Emit ECMAScript-standard-compliant class fields.
`--useUnknownInCatchVariables`	`boolean`	`true` if `strict`; `false` otherwise.
Default catch clause variables as `unknown` instead of `any`.
`--verbatimModuleSyntax`	`boolean`	`false`
Do not transform or elide any imports or exports not marked as type-only, ensuring they are written in the output file's format based on the 'module' setting.

Every option is fully explained in the TSConfig Reference.
Learn how to use a tsconfig.json file.
Learn how to work in an MSBuild project.