SimplyPNG API Documentation

Base URL

All API requests should be made to:

https://api.simplypng.app/api/v1

Features

• Fast Processing - Most images processed in under 5 seconds
• High Quality - AI-powered edge detection for clean results
• Simple API - Just send an image, get a transparent PNG
• Flexible Output - Get results as URL or base64
• Idempotency - Prevent duplicate processing with idempotency keys
• HEIC Support - Native support for iPhone photos (HEIC/HEIF)

Supported Image Formats

Image Input Methods

You can provide images in two ways:

Method 1: URL Input (Recommended)

Provide a public URL to your image. Best for large images and production use.

{
  "image": "https://your-storage.com/photo.jpg"
}

• No size limit
• Faster processing (no upload through API)
• Works with any public URL (S3, R2, CloudFront, etc.)

Method 2: Base64 Input

Send image data directly as a base64-encoded string. Good for small images and quick tests.

{
  "image": "data:image/png;base64,iVBORw0KGgo..."
}

• Maximum 4 MB (after decoding)
• Convenient for small images
• No external storage needed

Image Size Limits

💡 Tip: For images larger than 4MB (like 4K photos or HEIC files), upload to any storage service and use URL input. This is also faster since the image doesn't pass through the API server.

Rate Limits

Rate limits are based on your total API credits purchased, not subscription plan. Rate limit headers (X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset) are included in all responses.

HD Mode

For higher quality results, enable HD mode by setting options.hd_mode: true:

{
  "image": "https://your-storage.com/photo.jpg",
  "options": { "hd_mode": true }
}