The differences
- XAdES: the signature is XML. The file ends in .xades or .xml, and the document is inside it or next to it. Devices can't open it on their own.
- PAdES: the signature is stored inside the PDF. Any PDF app opens the document, but only some (such as Adobe Acrobat) show the signature.
- CAdES: a binary signature in a .sig, .p7m or .p7s file. As with XAdES, the document is inside the file or next to it.
Which one is better?
None: with a qualified signature they all have the same legal effect in the EU. PAdES is easiest for the recipient because it is a normal PDF. XAdES can sign any file, including XML forms from public offices, which is why Polish systems such as ePUAP use it.
Opening them
Choose a .xades, .xml, .sig, .p7m or PDF file at the top of the page. We show the document, the signer and whether the content has been changed.