Quick Glance
  • What are PAdES, CAdES, and XAdES?
  • PDF Advanced Electronic Signatures (PAdES)
  • Extensible Markup Language Advanced Electronic Signatures (XAdES)
  • Cryptographic Message Syntax Advanced Electronic Signatures (CAdES)
  • faqs

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What are PAdES, CAdES, and XAdES?

Electronic signatures are paperless, secure, tamper-proof alternatives to signing business documents with pen and paper. They help businesses sign, send, and manage their contracts and agreements from anywhere and at any time.

PAdES, CAdES, and XAdES are the commonly used electronic signature formats in the European Union. Let's learn more about them.

The primary difference between PAdES, CAdES, and XAdES lies in:

  • The type of documents you need to sign and
  • How you would like to view, access, and share the signed documents.

Using these differentiating factors, you can choose an electronic signature that works best for your organization.

PDF Advanced Electronic Signatures (PAdES)

PAdES allows you to affix a digital signature to a PDF file. You can also add a graphic signature in the form of an image, text, or drawing. The affixed AES can be verified via the file's signature panel using a PDF reader.

  • Ideal for businesses signing large volumes of PDFs
  • Graphic signatures visible
  • Previously added signatures remain valid

Extensible Markup Language Advanced Electronic Signatures (XAdES)

XML Advanced Electronic Signatures can be used to sign most file formats, including PDFs, PNG and JPG images, binary data (EXE), MP3, Single Euro Payments Area (SEPA) transactions, and more. XAdES are both human and computer-readable, and they provide two options for signing:

  • Encapsulated: An XML file with the signature and the document data
  • Detached: An XML file where the signature is separately created without modifying the document data
  • Automated signing by multiple people
  • Signing possible in most formats
  • Previously added signatures remain valid

Note that you cannot add a graphic signature visible to humans when using XAdES.

Cryptographic Message Syntax Advanced Electronic Signatures (CAdES)

When using CAdES, the signature is affixed to the document, and the document format becomes P7M. CAdES can be affixed to any file format, but they can only be read with software that can open P7M files.

Note that you cannot add a graphic signature that is visible to the human eye. You further cannot add multiple signatures on the same document; you have to affix a separate P7M envelope each time you add a signature.

  • Sign across file formats
  • Unique signature affixation envelopes for multiple signatures
  • Document and signature are within a single envelope

FAQs

  • Which is the best: PAdES, XAdES, or CAdES?

    All three types of AES are highly secure, tamper-proof, and able to identify the signer. The differences between these options lie in the file formats they allow and how they can be viewed, shared, and accessed. You choose the AES that best suits your needs based on these factors.

  • How secure are PAdES, CAdES, and XAdES?

    The standards for PAdES, XAdES, and CAdES are set by the European Telecommunications Standards Institute (ETSI) and ensure that they are highly secure. The usage of these AES also helps capture the signer's identity, guaranteeing the traceability and tamper-proof status of the signed documents.

  • Does Zoho Sign provides PAdES, CAdES, and XAdES?

    Zoho Sign is best suited for organizations that sign PDF files and provides PAdES.

Choose the best digital signature for your organization. Choose Zoho Sign.