Introduction to the PDF Blocks API
A secure, fast, stateless HTTP API for PDF operations — one PDF in, one PDF out, no SDK required.
PDF Blocks is a secure, fast, stateless HTTP API for working with PDF documents. Send a document, name an action, and get the processed PDF straight back in the response. There is no account state to manage, nothing is stored after a request returns, and there is no SDK to install — every action is a single authenticated HTTPS call you can make from any language.
The mental model
One PDF in, one PDF out. Every action is a pure transformation: it takes a
document (plus a few parameters), returns a new document, and keeps nothing. You
send multipart/form-data with your PDF in a file field, and a single-output
action answers 200 OK with application/pdf — the finished document as the
response body.
Because each output is itself a valid PDF, it is a valid input to the next action. That makes actions composable: merge several files, watermark the result, then encrypt it, each step feeding the next. See Chaining actions for how to build a pipeline without ever touching disk.
The action catalog
Seventeen actions, grouped by capability. Each links to its full reference.
Merge & Split
Combine an ordered list of PDFs into one.
Break into fixed-size chunks.
Break at a chosen page boundary.
Cap each part’s byte size.
Group pages by a pattern you define.
Watermarks
Passwords & security
Encrypt a document.
Decrypt a document with a known password.
Set permission flags.
Clear the permission flags.
Strip digital signatures.
Pages
Keep a page subset.
Drop a page subset.
Turn pages 90°, 180°, or 270°.
Flip the page order.
Rearrange pages into any order.
For the whole picture — the naming convention, how actions compose, and where each one lives — see the Actions overview.
What makes it different
- Fast. Actions are single-purpose transformations with no queues and no round trips. You send a request and stream the result straight to a file.
- Secure and stateless. Requests travel over HTTPS only and authenticate with a secret key. Documents are processed in-region and never stored — once the response is written, nothing remains.
- Regional data residency. The same catalog runs in ten regions, so your documents can be processed where your compliance needs them to be. Point a request at the region’s base URL and everything else is identical.
| Region | Base URL |
|---|---|
| Global | https://api.pdfblocks.com |
| United States | https://us.api.pdfblocks.com |
| US HIPAA | https://hipaa.api.pdfblocks.com |
| European Union | https://eu.api.pdfblocks.com |
| United Kingdom | https://uk.api.pdfblocks.com |
| Canada | https://ca.api.pdfblocks.com |
| Australia | https://au.api.pdfblocks.com |
| Japan | https://jp.api.pdfblocks.com |
| India | https://in.api.pdfblocks.com |
| Brazil | https://br.api.pdfblocks.com |
More regions are available on request. See Regions & data residency for the full details.