The Be Sure Blog

To change the port of a Next.js app, there are two ways:

Way One: package.json

In package.json add "-p 3001" to "dev" or "start", whether you want to change the port for development or production. your package.json may look like this now:

"scripts": {
    "dev": "next dev -p 3001",
    "build": "next build",
    "start": "next start",
    "lint": "next lint",
    "export": "next build && next export"
  },

When you run $ npm run dev, the URL will be http://localhost:3001

Way Two: Command line

When starting the development or production server, add "-- -p 3001" to the command, so it may be:

$ npm run start -- -p 3001

Same as before, the url will be http://localhost:3001