@capgo/capacitor-file-compressor

Compress and resize images on the device before upload, and convert between JPEG, PNG and WebP. Smaller files mean faster uploads and lower storage costs.

🤖 Building with an AI coding agent? Install Capgo skills so Claude Code, Codex, Cursor, Copilot, or Gemini CLI know how to install and use @capgo/capacitor-file-compressor in your Capacitor app: npx skills add Cap-go/capgo-skills. Then ask your agent: "Add @capgo/capacitor-file-compressor to my Capacitor app and wire it up." Agent setup guides · Hosted MCP

Key features

• One call: compressImage() resizes and compresses with your width, height and quality.
• Format conversion: output JPEG, PNG or WebP on Android and web. iOS adds HEIF or HEIC, and WebP needs iOS 14 or later.
• Smart sizing: keeps the aspect ratio and never upscales.
• Best-effort size: if the result is larger than the source, quality is lowered for lossy formats. PNG has no quality setting, so the output can still be larger.
• Privacy: EXIF metadata is removed during compression.
• Platforms: iOS, Android and Web. iOS uses ImageIO, Android uses Bitmap, web uses the canvas.

Why File Compressor?

A free, open-source alternative for client-side image compression:

• Format conversion - Convert HEIF, PNG, WebP, GIF, and more to JPEG, PNG, WebP, or HEIF
• Multiple formats - Broad input support with platform-specific output formats
• Quality control - Adjustable compression quality (0.0 - 1.0)
• Smart resizing - Automatic aspect ratio preservation without upscaling
• Cross-platform - Consistent API across iOS, Android, and Web
• Zero backend - All compression happens on the device

Essential for apps that need to optimize image uploads, reduce storage, or improve performance without server-side processing.

Documentation

The most complete doc is available here: https://capgo.app/docs/plugins/file-compressor/

Compatibility

Note: The major version of this plugin follows the major version of Capacitor. Use the version that matches your Capacitor installation (e.g., plugin v8 for Capacitor 8). Only the latest major version is actively maintained.

Install

You can use our AI-Assisted Setup to install the plugin. Add the Capgo skills to your AI tool using the following command:

npx skills add https://github.com/cap-go/capacitor-skills --skill capacitor-plugins

Then use the following prompt:

Use the `capacitor-plugins` skill from `cap-go/capacitor-skills` to install the `@capgo/capacitor-file-compressor` plugin in my project.

If you prefer Manual Setup, install the plugin by running the following commands and follow the platform-specific instructions below:

npm install @capgo/capacitor-file-compressor
npx cap sync

Format Conversion

The plugin accepts common image formats as input and converts them to the mimeType you request.

import { FileCompressor } from '@capgo/capacitor-file-compressor';

// Convert an iPhone HEIF photo to JPEG before upload
const result = await FileCompressor.compressImage({
  path: heifFileUri,
  width: 1920,
  height: 1080,
  quality: 0.7,
  mimeType: 'image/jpeg',
});

Note: EXIF metadata is removed during compression on all platforms.

API

• compressImage(...)
• getPluginVersion()
• Interfaces

Capacitor File Compressor Plugin interface for image compression.

compressImage(...)

compressImage(options: CompressImageOptions) => Promise<CompressImageResult>

Compresses an image file with specified dimensions and quality settings.

This method compresses images to reduce file size while maintaining acceptable quality. It supports resizing and format conversion across common image formats.

Supported input formats (platform decoder dependent): JPEG, PNG, WebP, GIF, BMP, TIFF, HEIF/HEIC

Supported output formats:

• iOS: image/jpeg, image/png, image/heif, image/heic, image/webp (iOS 14+)
• Android: image/jpeg, image/png, image/webp
• Web: image/jpeg, image/png, image/webp

Important Notes:

• EXIF metadata is removed during compression on all platforms
• Aspect ratio is automatically maintained if only one dimension is provided
• When both width and height are provided, the image fits inside that box without upscaling
• Compressed files are saved to temporary directories on native platforms
• If the encoded output would be larger than the source file, quality is reduced automatically while keeping the requested output format

Returns: Promise<CompressImageResult>

Since: 7.0.0

getPluginVersion()

getPluginVersion() => Promise<{ version: string; }>

Get the native Capacitor plugin version.

Returns the version of the native plugin implementation. Useful for debugging and ensuring compatibility.

Returns: Promise<{ version: string; }>

Since: 7.0.0

Interfaces

CompressImageResult

The result of compressing an image.

Contains either a file path (native platforms) or a Blob (web platform) depending on where the compression was performed.

CompressImageOptions

Options for compressing an image.

Configure the compression behavior including quality, dimensions, and output format. Platform-specific options are available for path (native) and blob (web).