Watermark PDFs via API

Stamp text across every page of a PDF document. Mark drafts, label confidential files, or brand documents with your company name - all through one API call.

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2 Credits per request

Custom Text, size, opacity

10 MB Max file size

Stamp every page in one request

Terminal

$ curl -X POST "https://qkconvert.dev/api/v1/doc/watermark" \
  -H "Authorization: Bearer sk_live_..." \
  -F "file=@contract.pdf" \
  -F 'options={"text":"DRAFT","opacity":0.3}' \
  -o contract-draft.pdf

# 200 OK - 110ms - watermarked across all 12 pages

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