# split-on-first [](https://travis-ci.com/sindresorhus/split-on-first) > Split a string on the first occurrence of a given separator This is similar to [`String#split()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/split), but that one splits on all the occurrences, not just the first one. ## Install ``` $ npm install split-on-first ``` ## Usage ```js const splitOnFirst = require('split-on-first'); splitOnFirst('a-b-c', '-'); //=> ['a', 'b-c'] splitOnFirst('key:value:value2', ':'); //=> ['key', 'value:value2'] splitOnFirst('a---b---c', '---'); //=> ['a', 'b---c'] splitOnFirst('a-b-c', '+'); //=> ['a-b-c'] ``` ## API ### splitOnFirst(string, separator) #### string Type: `string` The string to split. #### separator Type: `string` The separator to split on. ## Related - [split-at](https://github.com/sindresorhus/split-at) - Split a string at one or more indices ## License MIT © [Sindre Sorhus](https://sindresorhus.com)