# p-limit [![Build Status](https://travis-ci.org/sindresorhus/p-limit.svg?branch=master)](https://travis-ci.org/sindresorhus/p-limit) > Run multiple promise-returning & async functions with limited concurrency ## Install ``` $ npm install p-limit ``` ## Usage ```js const pLimit = require('p-limit'); const limit = pLimit(1); const input = [ limit(() => fetchSomething('foo')), limit(() => fetchSomething('bar')), limit(() => doSomething()) ]; (async () => { // Only one promise is run at once const result = await Promise.all(input); console.log(result); })(); ``` ## API ### pLimit(concurrency) Returns a `limit` function. #### concurrency Type: `number`
Minimum: `1` Concurrency limit. ### limit(fn) Returns the promise returned by calling `fn`. #### fn Type: `Function` Promise-returning/async function. ## Related - [p-queue](https://github.com/sindresorhus/p-queue) - Promise queue with concurrency control - [p-throttle](https://github.com/sindresorhus/p-throttle) - Throttle promise-returning & async functions - [p-debounce](https://github.com/sindresorhus/p-debounce) - Debounce promise-returning & async functions - [p-all](https://github.com/sindresorhus/p-all) - Run promise-returning & async functions concurrently with optional limited concurrency - [More…](https://github.com/sindresorhus/promise-fun) ## License MIT © [Sindre Sorhus](https://sindresorhus.com)