The **Promise.allSettled method** takes a list of promises as an input and returns a single promise. The returned promise will resolve after all the passed promises are either fulfilled or rejected.

# Code

const promise1 = Promise.resolve("Already Resolved");
const promise2 = new Promise((resolve, reject) => setTimeout( ()=> reject("Rejected after 100ms"), 100) );
const promises = [promise1, promise2];

let returnedPromise = Promise.allSettled(promises)
returnedPromise.then(values=>{
  console.log(values);
});

codemirror

console

In the above code, we have two promises: `promise1` is already resolved and `promise2` will be rejected after 100 milliseconds. Upon calling `Promise.allSettled` with these two promises, we will get a pending promise. Upon resolving it, we will get an array of promise results. 

In each fulfilled result, there are two properties: 
*  status with value fulfilled
* #key# value: the resolved value of the promise #key# 

In each rejected result, there are two properties: 
*  status with value rejected
* #key# error: the error message #key#

What is Promise.allSettled in JavaScript?

Handles multiple promises, returning a single promise with an array of results once all have settled.