A Promisable JSONP implementation

Usage no npm install needed!

<script type="module">
  import easyJsonp from 'https://cdn.skypack.dev/easy-jsonp';



A minimal and lightweight JSONP implementation which is used to be a kind of cross domain solutions.


  • Implement JSONP request from the browser

  • Combine URL query parameters by default behavior

  • Support the [Promise] API

  • Limit JSONP request period

  • Handle network error response


# using npm
npm i easy-jsonp
# using yarn
yarn add easy-jsonp
# using script target
<script src="jsonp.js"></script>


JSONP only support GET methods, same as easy-JSONP.

  • The code below show you how to use package as a dependency
// as a request dependency named jsonp
import jsonp from 'easy-jsonp'
const jsonp = require('easy-jsonp').default
  url: 'http://localhost',
  // global function named `callback` will be invoked when JSONP response
  callback: 'callback', // any different name from request module
  timeout: 3000,
  params: {
    // eg. ?key0=0&key1=1...
    key0: 0,
    key1: 1
  .then(res => console.log(res))
  .catch(err => console.error(err))

⚠️ Notice: Parameter callback value MUST NOT be same as request module name (eg. dependency named jsonp above code), otherwise request module only works once and function named value of parameter callback will be reset to null (internal implementation) which means the same name request module will be also reset unexpectedly.

For more customization capability, This package wouldn't convert callback to a new name to prevent unexpected reset.

  // custom configuration

⚠️ Notice: For same reason, parameter callback value MUST NOT be jsonp.


options parameter type required description
url String true JSONP request address
timeout Number false, default : 6000 milliseconds how long after timeout error is emitted. 0 to disable
callback String false, default : 'jsonpCallback'+Date.now() global callback function name which is used to handle JSONP response.
params Object false, default: {} other parameters in query string parameters


  • Uncaught SyntaxError: Unexpected token :error

It mostly doesn't support JSONP request when you are calling a JSON api. The difference between JSON api and JSONP is that JSON api response with an object like { num: 1 } (It will throw a error when client executed this response as a function. ). On the other hand, JSONP will respond with a function wrapped object like callback({ num: 1 }) and we will get what we need when client executed this response as a function.


If you like this plugin, scan the qrcodes below and send me some tips, thank you!