react-native-pdf-to-image

Convert PDF pages into PNG images from React Native.

The library exposes native methods for:

• converting a PDF file URI into cached PNG images
• converting a base64-encoded PDF into cached PNG images
• sending a base64 PDF payload to a socket printer

Features

• supports Android and iOS
• returns one output image path per PDF page
• writes generated images into the app cache directory
• works with local file URIs and copied document-picker files

Installation

npm install react-native-pdf-to-image

If you are using iOS, install pods after adding the package:

cd ios && pod install

Requirements

• React Native app with native modules enabled
• not supported in Expo Go
• on iOS, rebuild the app after installation

API

convert(uri: string): Promise<{ outputFiles: string[] | undefined }>

Converts a PDF referenced by a local URI into PNG files.

import { convert } from 'react-native-pdf-to-image';

const result = await convert('file:///path/to/document.pdf');

console.log(result.outputFiles);
// ['/.../Library/Caches/1713370000000-1_pdf.png', ...]

convertB64(base64Str: string, dpi: number): Promise<{ outputFiles: string[] | undefined }>

Converts a base64-encoded PDF string into PNG files.

The dpi argument is used as the target output width for the rendered page images.

import { convertB64 } from 'react-native-pdf-to-image';

const result = await convertB64(pdfBase64String, 1024);

console.log(result.outputFiles);
// ['/cache/...png', '/cache/...png']

printPDF(ip: string, port: number, base64Str: string): Promise<number>

Sends a base64-encoded PDF directly to a socket printer.

import { printPDF } from 'react-native-pdf-to-image';

await printPDF('192.168.0.25', 9100, pdfBase64String);

Example

The example app uses react-native-document-picker to let the user choose a PDF, copies it into the cache directory, then passes the copied file URI into convert().

import DocumentPicker from 'react-native-document-picker';
import { convert } from 'react-native-pdf-to-image';

const docs = await DocumentPicker.pick({
  type: DocumentPicker.types.pdf,
  copyTo: 'cachesDirectory',
});

if (docs.length) {
  const uri = docs[0]?.fileCopyUri || '';
  const result = await convert(uri);
  console.log(result.outputFiles);
}

Notes

• outputFiles contains absolute file paths for the generated PNG images.
• Generated files are written to the app cache directory, so you should move them if you need long-term storage.
• File URIs are the most reliable input for convert().
• Large PDFs can produce many images, so watch cache usage if you convert frequently.

Troubleshooting

If you see a linking error:

• run pod install on iOS
• rebuild the app after installing the package
• confirm you are not running inside Expo Go

If the example app fails during pod install on older React Native 0.72 setups, the bundled Boost mirror may need to be rewritten during CocoaPods install. The example project in this repository already includes that workaround.

Contributing

See the contributing guide to learn how to contribute to the repository and the development workflow.

License

MIT