Prompt
pdf signature api
Latest observation
If you mean an API to add/verify digital signatures in PDF files, there are a few common options depending on your language and needs:
Popular PDF signature APIs / libraries
- Adobe PDF Services API
Good for enterprise PDF workflows; supports signing-related workflows and document services. - iText 7
Very popular for PDF generation and digital signatures in Java/.NET (commercial licensing often required). - Apryse (PDFTron)
Strong SDK/API for PDF editing and signing across platforms. - Docusign / Adobe Sign / Dropbox Sign
Best if you need e-signatures (workflow, signing requests, audit trails) rather than embedded cryptographic PDF digital signatures. - PyPDF + cryptography / endesive (Python)
Useful for programmatic PDF digital signing in Python. - Apache PDFBox
Java library with PDF signing support.
Important distinction
- Digital signature in PDF = cryptographic signature embedded in the PDF, validates integrity and signer identity.
- E-signature workflow API = sends documents for people to sign electronically, often with audit trails.
If you want a REST API
Common approach:
- Upload PDF
- Apply signature/certificate
- Download signed PDF
If you want code examples
Tell me:
- Language: Python, Java, Node.js, .NET, PHP, etc.
- Goal: digital PDF signature or e-signature workflow
- Local or cloud API
I can then give you a working example.
Observation history
How did Obsurfable measure this prompt?
Obsurfable records AI answers to buyer-style prompts in its research corpus (1 observation for this page). Metrics are distributions over observations, not a single static ranking.
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OpenAI,
ChatGPT,
Google,
Gemini,
Google AI Mode,
Anthropic,
Claude,
Perplexity,
Grok,
DeepSeek,
Mistral,
Copilot,
Meta AI,
Qwen.
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