Content Services Team (Production)

Handshake Pilot (Prod)

$opt_dummy_attribute

Anonymous Users

Non-India Users

Pro Lite GTM (Production)

Non-Trial Users

Admin Users

Optimizely Test Users

Non-Student Users

Billing Update Modal (Production)

Mobile Wallet Internal Testers

Free Users

Optimizely-Generated Audience for Backwards Compatibility

anonymous

trial

admin

optimizely_test_user

student

free

Front-end engineers work closely with designers to make websites beautiful, functional, and fast.

Front-End Engineer

Learn how to use JavaScript — a powerful and flexible programming language for adding website interactivity.

Learn JavaScript


The `.toLowerCase()` method converts a string to lowercase letters in JavaScript.

## Syntax

```js
string.toLowerCase();
```

## Example 1

Converting uppercase letters to lowercase letters:

```js
console.log('HELLO WORLD'.toLowerCase());
// Output: hello world
```

## Example 2

Don't forget that `.toLowerCase()` doesn't actually change the original string.

```codebyte/js
var message = "sPoNgEbOb mEmE!"

message.toLowerCase()
console.log(message)

console.log(message.toLowerCase());
```


.charAt()

.concat()

.includes()

.indexOf()

.length

.repeat()

.replace()

.search()

.slice()

.split()

.startsWith()

.substring()

.toLowerCase()

.toString()

.toUpperCase()

.trim()

.valueOf()

JavaScript Terms

Back to JavaScript

JavaScript

.toLowerCase()

Syntax

Example 1

Example 2

All contributors

Learn JavaScript on Codecademy

Front-End Engineer

Learn JavaScript

Resources

Support

Resources

Support

Plans

Community

Subjects

Languages

Career building

Mobile

Mobile