Launched January 3, 2023
open-pdf-sign
Sign PDF files digitally from CLI
FreeOpen SourceCLI12,645 impressions#72 of its week
Easily add digital signatures to PDF files from command line.
No special certificates needed, you can just reuse your already existing certificates, e.g. from Let's Encrypt.
With support for LTV-enabled signatures and DocMDP
Built by
https://github.com/cproof
https://github.com/superphil0
CLI tool to digitally sign PDF files using existing certificates, with optional visible signatures.
- for
- Developers who need to add cryptographic signatures to PDFs via command line or web server.
- pricing
- free
- license
- Apache-2.0
- v0.3.0v0.3.0 TSA proxy support, Java 11, dependency upgradea year ago
- v0.2.1v0.2.1 Allow signing password-protected PDFs2 years ago
- v0.2.0v0.2.0: Allow only displaying image3 years ago
works withNginxNode.jsJava CLI
Key features
6 features of open-pdf-sign
- PAdES signatures — Create PAdES-B, PAdES-T, PAdES-LT or PAdES-LTA signatures for PDF authenticity.
- Visible/Invisible signatures — Add invisible signatures by default or customize visible signatures with images and text.
- Nginx integration — Automatically sign PDFs served by an Nginx server on the fly.
- Node.js module — Use the npm package to sign PDFs within Node.js applications.
- Cross-platform Java CLI — Runs on Windows, Linux and macOS with Java 11+.
- Open source license — Released under Apache 2.0, free to use and modify.
Use cases
- Sign PDFs generated by a web service before they are downloaded by users.
- Add a corporate logo as a visible signature on legal documents.
- Automatically sign every PDF served by an Nginx server to prove origin.
- Integrate PDF signing into a Node.js backend for on-demand document generation.
open-pdf-sign FAQ
What is open-pdf-sign used for?+
It automatically signs PDF documents, either individually via CLI or automatically on a web server.
Do I need a special certificate?+
No, any existing certificate/key can be used, including domain certificates like Let's Encrypt.
Which platforms are supported?+
It runs on Windows, Linux and macOS as a Java application (JRE 11+).
Can I add a visible signature with my own logo?+
Yes, you can include custom images and text for visible signatures using command-line options.
Is open-pdf-sign open source and free?+
Yes, it is released under the Apache 2.0 license and can be used and distributed freely.
Summarized by DevHunt from openpdfsign.org · Oct 4, 2026. Details may change; check the official site.