# lowercaseKeys > Convert each object key to lowercase.
## Usage ```javascript var lowercaseKeys = require( '@stdlib/utils/lowercase-keys' ); ``` #### lowercaseKeys( obj ) Converts each `object` key to lowercase, mapping the transformed keys to a new `object` having the same values. ```javascript var obj1 = { 'A': 1, 'B': 2 }; var obj2 = lowercaseKeys( obj1 ); // returns { 'a': 1, 'b': 2 } ```
## Notes - The function only transforms **own** properties. Hence, the function does **not** transform inherited properties. - The function **shallow** copies key values.
## Examples ```javascript var lowercaseKeys = require( '@stdlib/utils/lowercase-keys' ); var obj1 = { 'A': 'beep', 'B': 'boop', 'C': 'foo', 'D': 'bar' }; var obj2 = lowercaseKeys( obj1 ); console.dir( obj2 ); // => { 'a': 'beep', 'b': 'boop', 'c': 'foo', 'd': 'bar' } ```