API

The entire static surface lives on one class: TailwindPHP\tw (an alias of the internal Tailwind class). Every method is callable statically, and the inspection methods (properties, computedProperties, value, computedValue) all accept the input formats described at the bottom of this page.

For repeated work against the same CSS configuration, call tw::compile() once and reuse the returned TailwindCompiler.

use TailwindPHP\tw;

$css = tw::generate('<div class="flex items-center p-4 bg-blue-500">');

tw::generate()

public static function generate(string|array $input, string $css = '@import "tailwindcss";'): string

Parses content, extracts class candidates, and returns the generated CSS. The default $css is @import "tailwindcss";, which pulls in theme, preflight, and utilities. Returns string.

use TailwindPHP\tw;

// String input
$css = tw::generate('<div class="flex p-4">');

// String with custom CSS
$css = tw::generate('<div class="flex bg-brand">', '@import "tailwindcss"; @theme { --color-brand: #3b82f6; }');

// Array input with options
$css = tw::generate([
    'content' => '<div class="flex p-4">',
    'css' => '@import "tailwindcss";',
    'minify' => true,
]);

The array form accepts these keys:

Key	Type	Purpose
`content`	`string`	Content to scan for class candidates (required)
`css`	`string`	Input CSS with Tailwind directives (default `@import "tailwindcss";`)
`minify`	`bool`	Minify the output (default `false`)
`importPaths`	`string \| array \| callable \| null`	Load CSS from the filesystem with full `@import` resolution — see Importing CSS
`cache`	`bool \| string`	Enable file caching — see Caching
`cacheTtl`	`int`	Cache lifetime in seconds

tw::compile()

public static function compile(string $css = '@import "tailwindcss";', array $options = []): TailwindCompiler

Creates a reusable TailwindCompiler bound to the given CSS. Parsing and design-system construction happen once, so this is the efficient choice when generating CSS for many different content strings. Returns TailwindCompiler.

use TailwindPHP\tw;

// Default Tailwind
$compiler = tw::compile();

// Custom CSS
$compiler = tw::compile('@import "tailwindcss"; @theme { --color-brand: #3b82f6; }');

$css = $compiler->generate('<div class="flex p-4 bg-brand">');

See TailwindCompiler instance methods for the full instance surface.

tw::properties()

public static function properties(string|array $input, string $css = '@import "tailwindcss";'): array

Returns the raw CSS properties for a class, with CSS variables left unresolved. Returns array<string, string> (property name → value).

use TailwindPHP\tw;

tw::properties('p-4');
// ['padding' => 'calc(var(--spacing) * 4)']

tw::properties(['flex', 'items-center', 'p-4']);
// ['display' => 'flex', 'align-items' => 'center', 'padding' => 'calc(var(--spacing) * 4)']

tw::computedProperties()

public static function computedProperties(string|array $input, string $css = '@import "tailwindcss";'): array

Like properties(), but with every CSS variable resolved to a concrete value. Returns array<string, string>.

use TailwindPHP\tw;

tw::computedProperties('p-4');
// ['padding' => '1rem']

tw::computedProperties('text-blue-500');
// ['color' => 'oklch(.546 .245 262.881)']

tw::computedProperties(['flex', 'items-center', 'gap-4']);
// ['display' => 'flex', 'align-items' => 'center', 'gap' => '1rem']

tw::value()

public static function value(string|array $input, string $css = '@import "tailwindcss";'): ?string

Returns the raw value for a single utility class. Returns ?string — null if the utility is not found.

use TailwindPHP\tw;

tw::value('p-4');           // 'calc(var(--spacing) * 4)'
tw::value('text-blue-500'); // 'var(--color-blue-500)'

tw::computedValue()

public static function computedValue(string|array $input, string $css = '@import "tailwindcss";'): ?string

Returns the resolved value for a single utility class. Returns ?string — null if the utility is not found.

use TailwindPHP\tw;

tw::computedValue('p-4');           // '1rem'
tw::computedValue('text-blue-500'); // 'oklch(.546 .245 262.881)'
tw::computedValue('gap-4');         // '1rem'

tw::extractCandidates()

public static function extractCandidates(string $html): array

Extracts Tailwind class names from content (reads both class and className attributes). Returns array<string>.

use TailwindPHP\tw;

tw::extractCandidates('<div class="flex p-4" className="bg-blue-500">');
// ['flex', 'p-4', 'bg-blue-500']

tw::minify()

public static function minify(string $css): string

Minifies CSS: removes comments, collapses whitespace, shortens hex colors (#ffffff → #fff), drops units from zero values (0px → 0), and more. Returns string.

use TailwindPHP\tw;

$css = tw::generate('<div class="flex p-4">');
$minified = tw::minify($css);

See Caching & minification for the full set of optimizations.

tw::clearCache()

public static function clearCache(string|bool|null $cache = true): int

Deletes cached CSS files. Pass true (or omit) for the default cache directory, or a path string for a custom directory. Returns int — the number of files deleted.

use TailwindPHP\tw;

tw::clearCache();                  // default directory
tw::clearCache('/path/to/cache');  // custom directory

A standalone TailwindPHP\clearCache() function is also available.

tw::colors()

public static function colors(string $css = '@import "tailwindcss";'): array

Returns every color value from the theme. Returns array<string, string> (color name → computed value).

use TailwindPHP\tw;

tw::colors();
// ['red-500' => 'oklch(63.7% 0.237 25.331)', 'blue-500' => 'oklch(62.3% 0.214 259.815)', ...]

// With a custom theme
tw::colors('@import "tailwindcss"; @theme { --color-brand: #3b82f6; }');
// [..., 'brand' => '#3b82f6']

tw::breakpoints()

public static function breakpoints(string $css = '@import "tailwindcss";'): array

Returns every breakpoint value from the theme. Returns array<string, string> (breakpoint name → value).

use TailwindPHP\tw;

tw::breakpoints();
// ['sm' => '40rem', 'md' => '48rem', 'lg' => '64rem', 'xl' => '80rem', '2xl' => '96rem']

tw::breakpoints('@import "tailwindcss"; @theme { --breakpoint-xs: 20rem; }');
// ['xs' => '20rem', 'sm' => '40rem', ...]

tw::spacing()

public static function spacing(string $css = '@import "tailwindcss";'): array

Returns custom spacing values from the theme. Returns array<string, string> (spacing name → value).

use TailwindPHP\tw;

// TailwindCSS 4 uses a single --spacing base value rather than a --spacing-* namespace.
// This returns any custom --spacing-* values defined in the theme.
tw::spacing('@import "tailwindcss"; @theme { --spacing-huge: 10rem; }');
// ['huge' => '10rem']

Input formats

The inspection methods (generate, properties, computedProperties, value, computedValue) accept three input forms:

Format	Example
String only	`tw::generate('<div class="flex">')`
String + CSS string	`tw::generate('<div class="flex">', '@import "tailwindcss"; @theme { ... }')`
Array with `content` (+ optional `css`)	`tw::generate(['content' => '<div class="flex">', 'css' => '@import "tailwindcss";'])`

use TailwindPHP\tw;

// Format 1: string only
tw::properties('p-4');

// Format 2: string + CSS
tw::properties('bg-brand', '@import "tailwindcss"; @theme { --color-brand: #3b82f6; }');

// Format 3: array
tw::properties(['content' => 'p-4', 'css' => '@import "tailwindcss";']);

TailwindCompiler instance methods

The object returned by tw::compile() exposes the same inspection surface as the static class, bound to the CSS it was compiled with. Use it to avoid re-parsing the theme on every call.

public function generate(string $content): string
public function extractCandidates(string $html): array
public function properties(string|array $utilities): array
public function computedProperties(string|array $utilities): array
public function value(string $utility): ?string
public function computedValue(string $utility): ?string
public function minify(string $css): string
public function colors(): array
public function breakpoints(): array
public function spacing(): array

use TailwindPHP\tw;

$compiler = tw::compile('@import "tailwindcss"; @theme { --color-brand: #3b82f6; }');

$css        = $compiler->generate('<div class="flex p-4 bg-brand">');
$candidates = $compiler->extractCandidates('<div class="flex p-4 bg-brand">');

$compiler->properties('bg-brand');          // ['background-color' => 'var(--color-brand)']
$compiler->computedProperties('bg-brand');   // ['background-color' => '#3b82f6']
$compiler->value('bg-brand');                // 'var(--color-brand)'
$compiler->computedValue('bg-brand');        // '#3b82f6'

$minified = $compiler->minify($css);

$compiler->colors();        // all color values
$compiler->breakpoints();   // all breakpoint values
$compiler->spacing();       // custom spacing values

Advanced inspectors

For introspecting the compiled state directly:

public function getTheme(): Theme
public function getDesignSystem(): object
public function getCompiled(): array

$compiler->getTheme();        // Theme object with resolved values
$compiler->getDesignSystem(); // Design system: utilities, variants, etc.
$compiler->getCompiled();     // Raw compiled state array

These return internal structures; see Architecture for what they contain.

Caching

tw::generate() can cache compiled CSS to disk so identical inputs skip recompilation.

Option	Type	Default	Purpose
`cache`	`bool \| string`	`false`	`true` enables the default directory; a path string caches there
`cacheTtl`	`int`	none	Cache lifetime in seconds; expired entries are recompiled

use TailwindPHP\tw;

// Default directory: sys_get_temp_dir() . '/tailwindphp'
$css = tw::generate([
    'content' => '<div class="flex p-4">',
    'cache' => true,
]);

// Custom directory + TTL
$css = tw::generate([
    'content' => '<div class="flex p-4">',
    'cache' => '/path/to/cache',
    'cacheTtl' => 3600, // expire after 1 hour
]);

The cache key is derived from the content, the CSS configuration, and the minify option, so different inputs produce different cache files. Clear entries with tw::clearCache() or the standalone TailwindPHP\clearCache() function.

For the deeper guide, see Caching & minification.

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