Papiral
PixelForge
TabularSign PDF Online — Add Signature Image to PDF
Stamp a signature image onto the last page (or all pages) of your PDFs. Upload a ZIP with your signature PNG/JPG alongside the PDFs.
Pro feature. Upgrade to use Sign PDF. See plans →
1. Upload images
Drop images here or click to browse
JPEG, PNG, WebP, GIF, TIFF, AVIF — up to 10 files, 25 MB total
2. Configure settings
Include your signature image (signature.png or sig.jpg) in the ZIP alongside your PDFs.
What this tool does
Papiral places your signature image precisely on PDF pages — bottom-right corner of the last page by default, matching the most common signing convention. Adjust position, size, and opacity, and choose whether to sign just the last page or every page. Include your signature as signature.png or sig.jpg in the ZIP alongside your PDFs.
Problems it solves
- Adding a signature image to contracts before sending
- Stamping an approval signature onto invoice PDFs
- Signing multiple documents in a batch with one upload
- Adding a semi-transparent watermark-style signature
Example
Sign the last page of 10 contract PDFs with a signature image
Frequently asked questions
What image formats are supported for the signature?
JPEG and PNG. PNG with a transparent background works best — the transparency is preserved when stamped on the page.
Is this a cryptographic digital signature?
No — this tool stamps an image of your signature visually onto the PDF. It does not create a cryptographic signature or add PKI-based validation.
How do I include my signature in the ZIP?
Add your signature image (e.g. signature.png) to the same ZIP as your PDFs. Papiral will automatically find the first image file and use it as the signature.
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