lowerCase()

lowerCase(str): string

Converts string to lower case with space-separated words.

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Parameters

str: string | null | undefined

The string to convert.

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Returns: string

The lower cased string with words separated by spaces.

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See Also

String.toLowerCase() - MDN

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Since

2.0.0

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Performance

O(n) — charCode word splitting for short ASCII, regex for long/Unicode/emoji.

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Also known as

lowerCase (Lodash, es-toolkit) · ❌ (Remeda, Radashi, Ramda, Effect, Modern Dash, Antfu)

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Example

lowerCase('--Foo-Bar--');  // => 'foo bar'
lowerCase('fooBar');       // => 'foo bar'
lowerCase('__FOO_BAR__');  // => 'foo bar'

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How it works?

Converts string to space-separated lowercase words. Splits on case boundaries, underscores, hyphens, and emojis. Supports Unicode.

Conversion Examples

Input	Output
'--Foo-Bar--'	'foo bar'
'fooBar'	'foo bar'
'__FOO_BAR__'	'foo bar'
'ÑoñoCase'	'ñoño case'

Process

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Use Cases

Convert to lower case words 📌

Convert string to space-separated lowercase words. Useful for display labels or normalizing mixed-case input.

#lower#case#words#convert#split

lowerCase('fooBar');       // => 'foo bar'
lowerCase('__FOO_BAR__');  // => 'foo bar'
lowerCase('--Foo-Bar--');  // => 'foo bar'

Normalize text for display

Format programmatic identifiers into human-readable labels.

#normalize#text#display#format#label#design system

const label = lowerCase('backgroundColor');
// => 'background color'