Configure Digital Signature Appearance: Visible vs. Non-Visible Signatures

PSPDFKit offers comprehensive support for creating digital signatures, encompassing both visible and invisible signatures. The primary distinction between these two types lies in the customizable appearance aspect. Visible digital signatures, as the name suggests, are visually represented on a document, allowing users to easily identify and interact with them. Meanwhile, invisible digital signatures remain hidden within a document, leaving no visual trace. However, both types of signatures provide the same level of security and validity, ensuring the integrity of a digital document.

Visible Digital Signatures

To configure the appearance of a signed document using the PSPDFKit.Instance#signDocument function, provide a SignaturePreparationData object as the first argument and set a custom appearance field. This field is an object with the following properties:

{
  watermarkImage?: Blob | File,
  mode?: SignatureAppearanceMode,
  showSigner?: boolean,
  showReason?: boolean,
  showLocation?: boolean,
  showSignDate?: boolean,
  showWatermark?: boolean,
  showDateTimezone?: boolean
}

The main field to configure is mode, a property of type SignatureAppearanceMode, which determines the appearance of the signature. It can be set to one of the following values:

  • signatureOnly — Only the signature is displayed.

  • signatureAndDescription — Both the signature and a description are displayed. This is the default.

  • descriptionOnly — Only the description is displayed.

The table below shows an example of what each signature appearance mode looks like by default.

Signature Mode Example
signatureOnly Digital signature with signatureOnly appearance mode.
descriptionOnly Digital signature with descriptionOnly appearance mode.
signatureAndDescription Digital signature with signatureAndDescription appearance mode.

By default, the signature watermark is set to the PSPDFKit logo. If you want to remove the watermark, set showWatermark to false. If you want to use a different logo, customize the watermarkImage property. Supported file types for the logo are PDF, JPEG, and PNG.

The other properties (showSigner, showReason, showLocation, and showSignDate) configure whether the signer’s name, reason, location, and sign date should be displayed, respectively.

Invisible Digital Signatures

Invisible digital signatures don’t have any appearance. As described in the add a signature field guide, you can create an invisible digital signature by setting its boundingBox property to have a width and height of zero. This ensures that the signature remains hidden from view but still retains its cryptographic properties and validity. To see how invisible digital signatures function in practice, you can explore our demo.

Launch Demo