# decamelize-keys [](https://travis-ci.org/dsblv/decamelize-keys) > Convert object keys from camelCase to lowercase with a custom separator using [`decamelize`](https://github.com/sindresorhus/decamelize) *This project was forked from [`camelcase-keys`](https://github.com/sindresorhus/camelcase-keys) and converted to do the opposite* ## Install ```sh $ npm install --save decamelize-keys ``` ## Usage ```js const decamelizeKeys = require('decamelize-keys'); decamelizeKeys({fooBar: true}, '-'); //=> {'foo-bar': true} ``` ## API ### decamelizeKeys(input, [separator], [options]) ### input Type: `object` *Required* Object to decamelize. ### separator Type: `string` Default: `_` A string to insert between words. ### options Type: `object` #### separator Type: `string` Default: `_` Alternative way to specify [separator](#separator). #### exclude Type: `array` Default: `[]` Exclude keys from being decamelized. ## Related See [`camelcase-keys`](https://github.com/sindresorhus/camelcase-keys) for the inverse. ## License MIT © [Sindre Sorhus](http://sindresorhus.com), [Dmirty Sobolev](https://github.com/dsblv)