@thangdevalone/react-native-font-loader

A modern React Native library for dynamic font loading at runtime. Load fonts from base64, file path, or URL — with caching, progress tracking, and React hooks.

⚡ Supports both Old Architecture (Bridge) and New Architecture (TurboModules-ready)

Features

| Feature | react-native-dynamic-fonts | @thangdevalone/react-native-font-loader | |---|---|---| | Load from base64 | ✅ | ✅ | | Load from file path | ❌ | ✅ | | Load from URL | ❌ | ✅ | | Auto-detect source type | ❌ | ✅ | | Font caching | ❌ | ✅ | | Batch loading + progress | Basic | ✅ with callback | | Font metadata extraction | ❌ | ✅ | | Unload font | ❌ | ✅ (iOS) | | Cache management | ❌ | ✅ | | React Hooks | ❌ | ✅ useFont / useFonts | | TypeScript | ❌ | ✅ Full types | | New Architecture | ❌ | ✅ Compatible |

Installation

# npm
npm install @thangdevalone/react-native-font-loader

# yarn
yarn add @thangdevalone/react-native-font-loader

iOS

cd ios && pod install

Android

No additional setup required — the library auto-links.

Quick Start

Load a font from URL

import { loadFont } from '@thangdevalone/react-native-font-loader';

// Source type is auto-detected (base64, file, or URL)
const result = await loadFont({
  name: 'Roboto',
  source: 'https://fonts.example.com/Roboto-Regular.ttf',
});

// Use the font
<Text style={{ fontFamily: 'Roboto' }}>Hello World</Text>

Load from base64

import { loadFontFromBase64 } from '@thangdevalone/react-native-font-loader';

const result = await loadFontFromBase64('MyFont', base64String, 'ttf');

Load from file

import { loadFontFromFile } from '@thangdevalone/react-native-font-loader';

const result = await loadFontFromFile('MyFont', '/path/to/font.ttf');

React Hooks

useFont — Single font

import { useFont } from '@thangdevalone/react-native-font-loader';

function MyComponent() {
  const { loaded, error, fontFamily } = useFont({
    name: 'CustomFont',
    source: 'https://example.com/CustomFont.ttf',
  });

  if (!loaded) return <ActivityIndicator />;
  if (error) return <Text>Error: {error.message}</Text>;

  return <Text style={{ fontFamily }}>Loaded dynamically!</Text>;
}

useFonts — Multiple fonts with progress

import { useFonts } from '@thangdevalone/react-native-font-loader';

function App() {
  const { loaded, progress, fontFamilies } = useFonts([
    { name: 'Roboto-Regular', source: 'https://example.com/Roboto-Regular.ttf' },
    { name: 'Roboto-Bold', source: 'https://example.com/Roboto-Bold.ttf' },
  ]);

  if (!loaded) {
    return <Text>Loading fonts... {Math.round(progress * 100)}%</Text>;
  }

  return (
    <View>
      <Text style={{ fontFamily: 'Roboto-Regular' }}>Regular text</Text>
      <Text style={{ fontFamily: 'Roboto-Bold' }}>Bold text</Text>
    </View>
  );
}

API Reference

Core Functions

loadFont(options: FontLoadOptions): Promise<FontLoadResult>

Load a font from any source. The source type is auto-detected.

interface FontLoadOptions {
  name: string;        // Font family name to register
  source: string;      // base64 | file path | URL (auto-detected)
  type?: 'ttf' | 'otf'; // Auto-detected from extension if omitted
  cache?: boolean;     // Default: true
  forceReload?: boolean; // Skip cache, default: false
}

loadFonts(fonts, onProgress?): Promise<FontLoadResult[]>

Load multiple fonts with optional progress callback.

loadFontFromUrl(name, url, options?): Promise<FontLoadResult>

Load a font from a URL with optional headers and timeout.

loadFontFromFile(name, filePath): Promise<FontLoadResult>

Load a font from a local file path.

loadFontFromBase64(name, base64, type?): Promise<FontLoadResult>

Load a font from a base64-encoded string.

Font Management

isFontLoaded(fontName): boolean

Check if a font is loaded (synchronous).

getLoadedFonts(): string[]

Get all currently loaded font names.

unloadFont(fontName): Promise<boolean>

Unload a font. On iOS, this actually unregisters the font from the system. On Android, it removes the font from the cache.

clearFontCache(): Promise<void>

Clear all cached fonts and unload them.

getFontInfo(filePath): Promise<FontInfo>

Extract metadata from a font file.

interface FontInfo {
  familyName: string;     // e.g., "Roboto"
  fullName: string;       // e.g., "Roboto Bold"
  postScriptName: string; // e.g., "Roboto-Bold"
  style: string;          // e.g., "Regular", "Bold", "Italic"
  weight: number;         // CSS weight: 100-900
}

Platform Notes

iOS

• The name returned after loading is the font's actual PostScript name from the font file. Use this value for fontFamily in your styles.
• unloadFont() actually unregisters the font from CoreText.

Android

• The font is registered with React Native's ReactFontManager, so fontFamily works with the name you provide.
• Fonts are stored in the app's cache directory (cacheDir/rn_font_loader/).

Requirements

• React Native >= 0.71.0
• iOS >= 13.0
• Android minSdk >= 21

License

MIT