How can I update each dependency in package.json to the latest version?

I copied package.json from another project and now want to bump all of the dependencies to their latest versions since this is a fresh project and I don't mind fixing something if it breaks.

What's the easiest way to do this?

The best way I know is to run npm info express version and then update each dependency in package.json manually. There must be a better way.

{
  "name": "myproject",
  "description": "my node project",
  "version": "1.0.0",
  "dependencies": {
    "express": "^3.0.3", // how do I get these bumped to latest?
    "mongodb": "^1.2.5",
    "underscore": "^1.4.2"
  }
}

For Yarn-specific solutions, refer to this Stack Overflow question.

Solution

It looks like npm-check-updates is the only way to make this happen now.

npm i -g npm-check-updates
ncu -u
npm install

Or using npx (so you don't have to install a global package):

npx npm-check-updates -u
npm install

On npm <3.11:

Simply change every dependency's version to *, then run npm update --save. (Note: broken in recent (3.11) versions of npm).

Before:

  "dependencies": {
    "express": "*",
    "mongodb": "*",
    "underscore": "*",
    "rjs": "*",
    "jade": "*",
    "async": "*"
  }

After:

  "dependencies": {
    "express": "~3.2.0",
    "mongodb": "~1.2.14",
    "underscore": "~1.4.4",
    "rjs": "~2.10.0",
    "jade": "~0.29.0",
    "async": "~0.2.7"
  }

Of course, this is the blunt hammer of updating dependencies. It's fine if—as you said—the project is empty and nothing can break.

On the other hand, if you're working in a more mature project, you probably want to verify that there are no breaking changes in your dependencies before upgrading.

To see which modules are outdated, just run npm outdated. It will list any installed dependencies that have newer versions available.

For Yarn specific solution, refer to this Stack Overflow answer.