PDF Signature Library

Sign PDFs and add encryption

The Pdftools SDK makes adding signatures to PDFs easy. The SDK supports various types including approval, certification, and time-stamping. It offers robust validation tools, and allows customizable visual appearances. The encryption feature caters to diverse document security needs.
👇 Start Building with the free PDF SDK Experience Edition (in under 60 seconds)
See documentation
Also available via Nuget (.NET) and Maven (Java) package managers
MacOS
Windows Client
Linux

Need a full license key? Contact us

Review code samples for encrypting and signing

See all Pdftools SDK code samples
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Swift document processing, no watermarks
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Unlock exceptional support—connect with the Pdftools team
Get a pricing quote tailored to your specific requirements
Get a pricing quote tailored to your specific requirements

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