PDF Tools API

Use the PDF Tools API to work with existing PDFs. Merge files, reduce their size, or convert them to PDF/X. Provide publicly accessible PDF URLs or Base64-encoded files and receive the result as PDF bytes or a temporary download URL.

To generate PDFs from HTML, URLs, or templates and apply compression or PDF/X conversion in the same request, use the Conversion API.

Choose a PDF Tool

📄️ Merge PDFs

Combine PDF files in the order you specify.

📄️ Compress PDFs

Reduce file size with four compression levels.

📄️ Convert to PDF/X

Choose PDF/X-4 or PDF/X-1a and an ICC profile.

Try it in the Playground

Try all three tools without writing code in the Playground, available on every plan, including Free.

Get Started with the PDF Tools API

1. Get your API key from API Credentials in your Dashboard.
2. Open the guide for your chosen tool and choose how to provide your PDF: a publicly accessible HTTPS URL or a local file encoded as Base64.
3. Select Direct to receive PDF bytes or Sync to receive a download URL.
4. Send the request with your API key and PDF input. You can use the code examples in each tool’s guide.

All endpoints accept POST requests with an API-KEY header and Content-Type: application/json.

Input Files

Provide PDFs as publicly accessible HTTPS URLs or Base64-encoded files.

• Merge: Send 2–20 PDFs in the order you want them merged. You can mix URLs and Base64-encoded files in the same request.
• Compress and Convert to PDF/X: Send one PDF using either a URL or Base64.

URLs must point directly to the PDF. Redirects and private network addresses are not supported. Send only the Base64-encoded PDF data, without the data:application/pdf;base64, prefix. Encrypted, empty, and invalid PDFs are not supported.

Response Formats

Each PDF tool provides Direct and Sync endpoints. Choose the endpoint based on how you want to receive the result.

Format	Response	File Availability
Direct	PDF bytes (application/pdf)	Returned directly, without a download URL.
Sync	JSON with result metadata and a download URL when using default storage	Available for download for 24 hours with default storage, or uploaded to your S3-compatible bucket.

Both endpoints return a response after processing is complete. PDF Tools do not support Async requests or webhooks.

On paid plans, Sync endpoints support customS3PresignedUrl to upload the result to your own S3-compatible bucket. See Uploading to Your S3 Bucket for setup details.

See each tool’s guide for limits, credit usage, and error handling.