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import React, { useState } from 'react'; ^^^^^^ SyntaxError: Cannot use import statement outside a module [duplicate]

I've got an ApolloServer project that's giving me trouble, so I thought I might update it and ran into issues when using the latest Babel. My "index.js" is:
require('dotenv').config()
import {startServer} from './server'
startServer()
And when I run it I get the error
SyntaxError: Cannot use import statement outside a module
First I tried doing things to convince TPTB* that this was a module (with no success). So I changed the "import" to a "require" and this worked.
But now I have about two dozen "imports" in other files giving me the same error.
*I'm sure the root of my problem is that I'm not even sure what's complaining about the issue. I sort of assumed it was Babel 7 (since I'm coming from Babel 6 and I had to change the presets) but I'm not 100% sure.
Most of what I've found for solutions don't seem to apply to straight Node. Like this one here:
ES6 module Import giving "Uncaught SyntaxError: Unexpected identifier"
Says it was resolved by adding "type=module" but this would typically go in the HTML, of which I have none. I've also tried using my project's old presets:
"presets": ["es2015", "stage-2"],
"plugins": []
But that gets me another error: "Error: Plugin/Preset files are not allowed to export objects, only functions."
Here are the dependencies I started with:
"dependencies": {
"#babel/polyfill": "^7.6.0",
"apollo-link-error": "^1.1.12",
"apollo-link-http": "^1.5.16",
"apollo-server": "^2.9.6",
"babel-preset-es2015": "^6.24.1",

Verify that you have the latest version of Node.js installed (or, at least 13.2.0+). Then do one of the following, as described in the documentation:
Option 1
In the nearest parent package.json file, add the top-level "type" field with a value of "module". This will ensure that all .js and .mjs files are interpreted as ES modules. You can interpret individual files as CommonJS by using the .cjs extension.
// package.json
{
"type": "module"
}
Option 2
Explicitly name files with the .mjs extension. All other files, such as .js will be interpreted as CommonJS, which is the default if type is not defined in package.json.

If anyone is running into this issue with TypeScript, the key to solving it for me was changing
"target": "esnext",
"module": "esnext",
to
"target": "esnext",
"module": "commonjs",
In my tsconfig.json. I was under the impression "esnext" was the "best", but that was just a mistake.

For those who were as confused as I was when reading the answers, in your package.json file, add
"type": "module"
in the upper level as show below:
{
"name": "my-app",
"version": "0.0.0",
"type": "module",
"scripts": { ...
},
...
}

According to the official documentation:
import statements are permitted only in ES modules. For similar functionality in CommonJS, see import().
To make Node.js treat your file as an ES module, you need to (Enabling):
add "type": "module" to package.json
add "--experimental-modules" flag to the Node.js call

I ran into the same issue and it's even worse: I needed both "import" and "require"
Some newer ES6 modules works only with import.
Some CommonJS works with require.
Here is what worked for me:
Turn your js file into .mjs as suggested in other answers
"require" is not defined with the ES6 module, so you can define it this way:
import { createRequire } from 'module'
const require = createRequire(import.meta.url);
Now 'require' can be used in the usual way.
Use import for ES6 modules and require for CommonJS.
Some useful links: Node.js's own documentation. difference between import and require. Mozilla has some nice documentation about import

I had the same issue and the following has fixed it (using Node.js 12.13.1):
Change .js files extension to .mjs
Add --experimental-modules flag upon running your app.
Optional: add "type": "module" in your package.json
More information: https://nodejs.org/api/esm.html

First we'll install #babel/cli, #babel/core and #babel/preset-env:
npm install --save-dev #babel/cli #babel/core #babel/preset-env
Then we'll create a .babelrc file for configuring Babel:
touch .babelrc
This will host any options we might want to configure Babel with:
{
"presets": ["#babel/preset-env"]
}
With recent changes to Babel, you will need to transpile your ES6 before Node.js can run it.
So, we'll add our first script, build, in file package.json.
"scripts": {
"build": "babel index.js -d dist"
}
Then we'll add our start script in file package.json.
"scripts": {
"build": "babel index.js -d dist", // replace index.js with your filename
"start": "npm run build && node dist/index.js"
}
Now let's start our server.
npm start

I Tried with all the methods, but nothing worked.
I got one reference from GitHub.
To use TypeScript imports with Node.js, I installed the below packages.
1. npm i typescript --save-dev
2. npm i ts-node --save-dev
Won't require type: module in package.json
For example,
{
"name": "my-app",
"version": "0.0.1",
"description": "",
"scripts": {
},
"dependencies": {
"knex": "^0.16.3",
"pg": "^7.9.0",
"ts-node": "^8.1.0",
"typescript": "^3.3.4000"
}
}

Step 1
yarn add esm
or
npm i esm --save
Step 2
package.json
"scripts": {
"start": "node -r esm src/index.js",
}
Step 3
nodemon --exec npm start

Node v14.16.0
For those who've tried .mjs and got:
Aviator#AW:/mnt/c/Users/Adrian/Desktop/Programming/nodejs_ex$ node just_js.mjs
file:///mnt/c/Users/Adrian/Desktop/Programming/nodejs_ex/just_js.mjs:3
import fetch from "node-fetch";
^^^^^
SyntaxError: Unexpected identifier
and who've tried import fetch from "node-fetch";
and who've tried const fetch = require('node-fetch');
Aviator#AW:/mnt/c/Users/Adrian/Desktop/Programming/nodejs_ex$ node just_js.js
(node:4899) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
/mnt/c/Users/Adrian/Desktop/Programming/nodejs_ex/just_js.js:3
import fetch from "node-fetch";
^^^^^^
SyntaxError: Cannot use import statement outside a module
and who've tried "type": "module" to package.json, yet continue seeing the error,
{
"name": "test",
"version": "1.0.0",
"description": "to get fetch working",
"main": "just_js.js",
"type": "module",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"author": "",
"license": "MIT"
}
I was able to switch to axios without a problem.
import axios from 'axios'; <-- put at top of file.
Example:
axios.get('https://www.w3schools.com/xml/note.xml').then(resp => {
console.log(resp.data);
});

I found the 2020 update to the answer in this link helpful to answering this question as well as telling you WHY it does this:
Using Node.js require vs. ES6 import/export
Here's an excerpt:
"Update 2020
Since Node v12, support for ES modules is enabled by default, but it's still experimental at the time of writing this. Files including node modules must either end in .mjs or the nearest package.json file must contain "type": "module". The Node documentation has a ton more information, also about interop between CommonJS and ES modules."

I'm new to Node.js, and I got the same issue for the AWS Lambda function (using Node.js) while fixing it.
I found some of the differences between CommonJS and ES6 JavaScript:
ES6:
Add "type":"module" in the package.json file
Use "import" to use from lib.
Example: import jwt_decode from jwt-decode
Lambda handler method code should be define like this
"exports.handler = async (event) => { }"
CommonJS:
Don't add "type":"module" in the package.json file
Use "require" to use from lib.
Example: const jwt_decode = require("jwt-decode");
The lambda handler method code should be defines like this:
"export const handler = async (event) => { }"

In my case. I think the problem is in the standard node executable. node target.ts
I replaced it with nodemon and surprisingly it worked!
The way using the standard executable (runner):
node target.ts
The way using the nodemon executable (runner):
nodemon target.ts
Do not forget to install nodemon with npm install nodemon ;P
Note: this works amazing for development. But, for runtime, you may execute node with the compiled js file!

To use import, do one of the following.
Rename the .js file to .mjs
In package.json file, add {type:module}

If you are using ES6 JavaScript imports:
install cross-env
in package.json change "test": "jest" to "test": "cross-env NODE_OPTIONS=--experimental-vm-modules jest"
more in package.json, add these:
...,
"jest": {
"transform": {}
},
"type": "module"
Explanation:
cross-env allows to change environment variables without changing the npm command. Next, in file package.json you change your npm command to enable experimental ES6 support for Jest, and configure Jest to do it.

This error also comes when you run the command
node filename.ts
and not
node filename.js
Simply put, with the node command we will have to run the JavaScript file (filename.js) and not the TypeScript file unless we are using a package like ts-node.

If you want to use BABEL, I have a simple solution for that!
Remember this is for nodejs example: like an expressJS server!
If you are going to use react or another framework, look in the babel documentation!
First, install (do not install unnecessary things that will only trash your project!)
npm install --save-dev #babel/core #babel/node
Just 2 WAO
then config your babel file in your repo!
file name:
babel.config.json
{
"presets": ["#babel/preset-env"]
}
if you don't want to use the babel file, use:
Run in your console, and script.js is your entry point!
npx babel-node --presets #babel/preset-env -- script.js
the full information is here; https://babeljs.io/docs/en/babel-node

I had this error in my NX workspace after upgrading manually. The following change in each jest.config.js fixed it:
transform: {
'^.+\\.(ts|js|html)$': 'jest-preset-angular',
},
to
transform: {
'^.+\\.(ts|mjs|js|html)$': 'jest-preset-angular',
},

I had this issue when I was running migration
Its es5 vs es6 issue
Here is how I solved it
I run
npm install #babel/register
and add
require("#babel/register")
at the top of my .sequelizerc file my
and go ahead to run my sequelize migrate.
This is applicable to other things apart from sequelize
babel does the transpiling

Just add --presets '#babel/preset-env'.
For example,
babel-node --trace-deprecation --presets '#babel/preset-env' ./yourscript.js
Or
in babel.config.js
module.exports = {
presets: ['#babel/preset-env'],
};

To make your import work and avoid other issues, like modules not working in Node.js, just note that:
With ES6 modules you can not yet import directories. Your import should look like this:
import fs from './../node_modules/file-system/file-system.js'

For people coming to this thread due to this error in Netlify functions even after adding "type": "module" in package.json file, update your netlify.toml to use 'esbuild'. Since esbuild supports ES6, it would work.
[functions]
node_bundler = "esbuild"
Reference:
https://docs.netlify.com/functions/build-with-javascript/#automated-dependency-bundling

The documentation is confusing. I use Node.js to perform some local task in my computer.
Let's suppose my old script was test.js. Within it, if I want to use
import something from "./mylocalECMAmodule";
it will throw an error like this:
(node:16012) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
SyntaxError: Cannot use import statement outside a module
...
This is not a module error, but a Node.js error. Forbid loading anything outside a 'module'.
To fix this, just rename your old script test.js into test.mjs.
That's all.

My solution was to include babel-node path while running nodemon as follows:
nodemon node_modules/.bin/babel-node index.js
You can add in your package.json script as:
debug: nodemon node_modules/.bin/babel-node index.js
NOTE: My entry file is index.js. Replace it with your entry file (many have app.js/server.js).

I had the same problem when I started to use Babel... But later, I
had a solution... I haven't had the problem any more so far...
Currently, Node.js v12.14.1, "#babel/node": "^7.8.4", I use babel-node and nodemon to execute (Node.js is fine as well..)
package.json: "start": "nodemon --exec babel-node server.js "debug": "babel-node debug server.js"!! Note: server.js is my entry
file, and you can use yours.
launch.json. When you debug, you also need to configure your launch.json file "runtimeExecutable":
"${workspaceRoot}/node_modules/.bin/babel-node"!! Note: plus
runtimeExecutable into the configuration.
Of course, with babel-node, you also normally need and edit another file, such as the babel.config.js/.babelrc file

In case you're running nodemon for the Node.js version 12, use this command.
server.js is the "main" inside package.json file, replace it with the relevant file inside your package.json file:
nodemon --experimental-modules server.js

I recently had the issue. The fix which worked for me was to add this to file babel.config.json in the plugins section:
["#babel/plugin-transform-modules-commonjs", {
"allowTopLevelThis": true,
"loose": true,
"lazy": true
}],
I had some imported module with // and the error "cannot use import outside a module".

If you are using node, you should refer to this document. Just setup babel in your node app it will work and It worked for me.
npm install --save-dev #babel/cli #babel/core #babel/preset-env

When I used sequelize migrations with npx sequelize db:migrate, I got this error, so my solution for this was adding the line require('#babel/register'); into the .sequelizerc file as the following image shows:
Be aware you must install Babel and Babel register.

Wrong MIME-Type for JavaScript Module Files
The common source of the problem is the MIME-type for "Module" type JavaScript files is not recognized as a "module" type by the server, the client, or the ECMAScript engine that process or deliver these files.
The problem is the developers of Module JavaScript files incorrectly associated Modules with a new ".mjs" (.js) extension, but then assigned it a MIME-type server type of "text/javascript". This means both .js and .mjs types are the same. In fact the new type for .js JavaScript files has also changed to "application/javascript", further confusing the issue. So Module JavaScript files are not being recognized by any of these systems, regardless of Node.js or Babel file processing systems in development.
The main problem is this new "module" subtype of JavaScript is yet known to most servers or clients (modern HTML5 browsers). In other words, they have no way to know what a Module file type truly is apart from a JavaScript type!
So, you get the response you posted, where the JavaScript engine is saying it needs to know if the file is a Module type of JavaScript file.
The only solution, for server or client, is to change your server or browser to deliver a new Mime-type that trigger ES6 support of Module files, which have an .mjs extension. Right now, the only way to do that is to either create a HTTP content-type on the server of "module" for any file with a .mjs extension and change your file extension on module JavaScript files to ".mjs", or have an HTML script tag with type="module" added to any external <script> element you use that downloads your external .js JavaScript module file.
Once you fool the browser or JavaScript engines into accepting the new Module file type, they will start doing their scripting circus tricks in the JS engines or Node.js systems you use.

Using Browserify with a config file instead of long CLI command

For Babel there is a .babelrc file, which contains all parameters needed for Babel to work, so you can just use babel index.js and this is working like specified in .babelrc, for example:
// .babelrc file
{
"presets": ["react"]
}
smroot#whatever: ~/project $ babel index.js
works the same way as:
smroot#whatever: ~/project $ babel index.js --presets react
Is there something similar to this for Browserify, so:
smroot#whatever: ~/project $ browserify index.js -o bundle/index.js -t [ babelify --presets [ react ] ]
could be replaced with just:
smroot#whatever: ~/project $ browserify index.js
and a config file for this?

#the_cheff 's solution is great, and It's also possible to define the parameters you need directly from package.json file without creating and npm script.
what you need is a new key "browserify" this way
"browserify": {
"transform": [
[
"babelify",
{
"presets": [
"#babel/preset-env"
]
}
]
]
}
and through the CLI just run:
browserify script.js > build/bundle.js

As #azium suggests in the comment you could create a npm script to handle this.
Open you package.json file and find (or create) the scripts section.
Then insert the command here with some name you would like.
"scripts": {
"browserify": "browserify index.js -o bundle/index.js -t [ babelify --presets [ react ] ]"
}
You can now run it with npm run browserify
Otherwise you could use a task runner like gulp to handle this. In general if you have multiple tasks like running bable, browserify, sass, less, or need to move files around, an actual task runner might come in handy.

running npm run build when installing Babel does not add file to output

after the Babel Setup, I was following a longa a video series in laracasts, I ecountered this problem:
Created a folder, inside the folder did the babel installation via npm in the command line,
I then created a person.js file for the demo to try it..
After setting up babel, the package.json file was edited and the following has been added:
{
"devDependencies": {
"babel-cli": "^6.26.0",
"babel-preset-env": "^1.6.0"
},
"scripts": {
"build": "babel src -d output"
}
}
and also added two folders a src folder
inside the person.js i added:
class Person {
constructor(name){
this.name = name;
}
}
this is the file image
After running this command in the command line i should get :
num run build
it doesnt add any files to the src folder or the output folder
I tried to look at youtube and answers in here couldn't find a solution
Solution provided by #loganfsmyth
Thank you very much, it worked I had 3 issues cleared npm cache using
'npm cache clean --force' 2. I moved the folder as you said to the src
folder, 3. I installed npm again using 'install npm' and it worked
perfectly thank you

babel src -d output
says
Compile the src folder and put the result in the output folder.
Since your Person.js file is not in the src folder, it has no effect.

Babili minifies but does not transpile

I am stuck with babili.
I need to transpile, then minify the javascript that is written in ES6. So I installed the package using:
npm install babili --save-dev
and made .babelrc file containing a preset:
{"presets": ["es2015"]}
Now I tried the following command
./node_modules/.bin/babili public/js/rt.socket.js --out-file public/test.min.js
It does give a minified but doesn't transpile. What could be the reason for this?
`

Babili does not use .babelrc. Per the README:
Note that, because the babili command uses the default preset with no-babelrc, you cannot set any non-default options in the preset's plugins with this command. To do this, you can use the babel command with the options set in a .babelrc. See the preset docs for more information on how to do this.
The solution is to instead use Babel with the babel-preset-babili preset, as described in the Babel preset section of the README (which assumes that you've already installed Babel):
Install
npm install babel-preset-babili --save-dev
Usage
You'll most likely want to use it only in the production environment.
Check out the env
docs for more help.
Options specific to a certain environment are merged into and overwrite non-env specific options.
.babelrc:
{
"presets": ["es2015"],
"env": {
"production": {
"presets": ["babili"]
}
}
}
Then you'll need to set the env variable which could be something like
BABEL_ENV=production npm run build

UglifyJS - convert all .js in a folder

I was wondering if anyone could help, I'm attempting to finish off my build process which currently transpiles es6 > es5 using babel, After that has completed I want to use uglifyJS to recursively minify all my .js files using just NPM scripts (no grunt or gulp please).
What I desire;
Convert all .js in folder to es5
Minify all .js files in a given folder using uglify
Create source maps
Copy out to a new folder
My current setup;
Converts all .js to es5
Minify all es5 .js files (However no sourcemaps are created, also the es5 js files are replaced as theres no support to move to another folder)
I've tried: https://www.npmjs.com/package/recursive-uglifyjs and https://www.npmjs.com/package/uglifyjs-folder but these both seem unable to perform the build steps I need
Here is my package.json scripts section
"babel": "babel js_uncompiled --out-dir js_uncompiled/es5 --source-maps && npm run npm:uglify",
"build": "npm run babel",
"uglify": "recursive-uglifyjs js_uncompiled/es5"
You can find a link to my full package.json here : http://pastebin.com/4UHZ1SGM
Thanks

EDITED: included info from comments
So, now uglifyjs-folder has the option of passing a config file so you can run all uglify's commands, but on a whole folder (and you can transpile to ES5 using harmony - as stated in comments).
Note this is better than doing so manually with cat or other shell commands, since uglifyjs-folder can generate a single output file (concatenated) and is simpler to use.
Run uglifyjs-folder "%CD%" --config-file "uglify.config.json" --output "folder" -e where the config file (in the root folder of project) contains for example (not all options needed):
{
"compress": true,
"mangle": true,
"sourceMap": {
"base": "input/path/",
"content": "input/sourcemap",
"filename": "{file}.min.js",
"includeSources": true,
"root": "original/source/path",
"url": "source/path"
}
}
Obs.: currently there is one open issue by myself because source-mapping is resulting in error. Once the issue is solved I will update my answer here.
UPDATE: ok, issue solved, version 1.5 released! Code above updated