SyntaxError: Cannot use import statement outside a module

The file uses import, but whatever is running it thinks it is an old-style CommonJS script (or, in a browser, a classic script). Tell the runtime the file is an ES module, or stop mixing the two systems.

Two module systems

The error means an import line landed in code the runtime is treating as the left-hand column.

Fix in Node

// package.json (nearest one to the file)
{
  "type": "module"
}

Or rename just that file to file.mjs. After switching, the reverse problems appear: require is not defined in ES module scope (use import, or createRequire from node:module), __dirname is not defined (use import.meta.dirname on Node 20.11+, or path.dirname(fileURLToPath(import.meta.url))), and relative imports need the extension: import './util.js', not './util'. Recent Node versions (22.12+) can also require() many ES modules, which softens some of this.

Validate the edited package.json in the JSON formatter: a stray comma there produces a different, more confusing error.

Fix in the browser

<!-- wrong: classic script -->
<script src="/app.js"></script>
<!-- right -->
<script type="module" src="/app.js"></script>

Module scripts are deferred automatically, run in strict mode, and must be served over HTTP(S) with a JavaScript MIME type. Opening the page from file:// triggers a CORS error instead, so use a local dev server. Bare imports like import React from 'react' do not work in the browser without a bundler (Vite, esbuild) or an import map.

Fix in TypeScript and ts-node

• The compiled output must match how Node runs it. Modern setups use "module": "NodeNext" and "moduleResolution": "NodeNext" in tsconfig.json, which follows "type" in package.json.
• ts-node in an ESM project needs its ESM loader (node --loader ts-node/esm), or switch to tsx, which handles both without config.
• Node 22.6+ can run simple .ts files directly with type stripping; the same "type" rules apply.

Fix in Jest

Jest runs tests as CommonJS by default. Either let Babel or ts-jest transform import into require, or run Jest in native ESM mode (NODE_OPTIONS=--experimental-vm-modules npx jest). When the failing file is inside node_modules (an ESM-only package), add it to transformIgnorePatterns exceptions, or move to Vitest, which is ESM-first.

When it is inside a dependency

If the stack trace points into node_modules/some-package, that package became ESM-only in a major version. Options: import it from an ESM file, use dynamic await import('some-package') from CJS, or pin the last CommonJS major. Compare the two lockfiles in the text diff tool to see which version jumped.

Related

npm ERR! code ENOENT · ModuleNotFoundError (Python) · Node OpenSSL digital envelope error · Refused to execute inline script (CSP) · npm ERR! code ELIFECYCLE · Module not found: Can't resolve · Cannot find module (Node)

Questions

Published 5 November 2026.