← Images to PDF

Turn images into a PDF with curl

Combine photos, scans or receipts into one PDF, one image per page, in the order sent. Here is the whole call with curl, with the output it produced when we ran it.

Before you start

An API key. Create a free account; it comes with free tokens every month. Put the key in an environment variable so it stays out of your code: export BLOODWEB_KEY=your_key
curl 7.76 or later (for --fail-with-body, which makes curl stop on an error and still show the reason).
The input files in the same folder: receipt1.jpg, receipt2.jpg. Use your own; those are the names the code expects.

The code

Save it as images-to-pdf.sh and run bash images-to-pdf.sh.

curl -sS --fail-with-body \
  -H "Authorization: Bearer $BLOODWEB_KEY" \
  -F "files[]=@receipt1.jpg" \
  -F "files[]=@receipt2.jpg" \
  https://bloodweb.net/api/v1/images-to-pdf \
  -o receipts.pdf

What you get

Tested 19 October 2026: this exact code ran against our test copy of the API, which runs the same service code as bloodweb.net, and produced this.

It writes receipts.pdf: a PDF, 2 pages, 79 KB.

The Images to PDF output, page 1 — Page 1 of the result.

Change the call

Every option the Images to PDF takes. Add or change them the same way as the ones in the code.

page: Paper size, or fit to make each page the size of its image. One of: A4, Letter, Legal, A5, fit.
margin: Margin in millimetres (ignored for fit).
quality: JPEG quality of the images inside the PDF.

If it fails

A failed call is not charged. The answer is JSON with an error object; curl stops with an error, and that JSON lands in receipts.pdf instead of the result, so open it as text to read the reason. The usual ones:

401 missing_key or invalid_key: BLOODWEB_KEY is not set in the shell that runs the code, or the key was revoked.
415 unsupported_type: the file is not a type this service reads. The type is read from the file itself, so renaming a file does not change it.
413 file_too_large: the file is over the limit on the service page.
402 insufficient_tokens: the balance does not cover the call. Top up in the dashboard.
429 rate_limited: too many calls at once. Wait the seconds in the Retry-After header and send it again.

Every code and its fix is in the docs.

The Images to PDF page: every option, the limits, and Try it now in your browser.
Getting started: keys, errors and rate limits for all the services.