Main page - FreeTSA - Guide: How to sign PDF documents files with time stamp
In this guide you can learn on how to apply an external Time Stamp, from FreeTSA trusted time stamping, when you are applying an Digital Signature to your PDF document.Using this time stamp server helps you prove to others that the document did exist at that date and hour, so it is very useful in certain circumstances.
For legally binding time stamp, you need to check applicable law, in order to know, what time stamping authorities, are acceptable as valid in your area.
Using several Time Stamping services (one at a time) makes your documents more resistant to possible future problems in current Time Stamping Services (hacking, bad behavior from the certification authorities, and others). You do have to save the documents in different folders or name the documents differently to know which of the Time Stamp Services you have applied.
The URL of the service is: https://freetsa.org/tsr
The supported hashes are: md4 / md5 / rmd160 / sha / sha1 / sha224 / sha256 / sha384 / sha512
FreeTSA recommends that users choose SHA512 (SHA-512) when software or hardware gives that option, because is considered the most secure of the hashes currently available.
Need a Private Certificate Key to sign your PDF documents? Read more here.
Software is being update very fast so don't be surprise if the software instructions bellow no longer apply to newer versions coming out in the future (please check the documentation of that program if that happens).
- XolidoSign 2.2.1.x instructions here - (Free)
- Libre Office 5 instructions here - (Free)
- JSignPdf 1.6.x instructions here - (Free)
- PDF Creator 2.x instructions here - (Free version available)
- PDF Signer 8.x instructions here - (Commercial - Fully functional 30 days trial available)
See two signed PDF documents with FreeTSA service.
Always test to see if everything works fine. If something is not working, use your favorite search engine to find the answer.
Last update: October 2, 2015 (Author: Joao).