PromiseallSettled

Promise.allSettled is a Promise utility that accepts an iterable of promises (and/or values) and returns a single promise that resolves after all input promises have settled, either fulfilled or rejected. When fulfilled, the returned value is an array describing the outcome of each input in the same order as provided. Each element is an object of the form { status: 'fulfilled', value: ... } or { status: 'rejected', reason: ... }.

Unlike Promise.all, which rejects as soon as one input rejects, allSettled waits for every input to settle. Non-promise values are treated as fulfilled, with their value reflected in the corresponding array element. It was standardized in ES2020 and is supported in modern browsers and in Node.js (12+).

Common use cases include performing multiple asynchronous operations in parallel and collecting all results, including failures, for reporting or aggregated processing. This avoids the need to short-circuit on the first failure.

Example:

Promise.allSettled([Promise.resolve(1), Promise.reject(new Error('oops')), 3]).then(results => console.log(results));

This prints an array like:

[

{ status: 'fulfilled', value: 1 },

{ status: 'rejected', reason: Error('oops') },

{ status: 'fulfilled', value: 3 }

]

See also: Promise.all, Promise.any, Promise.race.