What Is a Signature Field?

A Signature Field is the most common field type in Yousign. It represents the visible signature on a document and is essential for the signing process.

⚠️The visible Signature Field on the document is not the actual cryptographic signature. The cryptographic signature is embedded in the PDF document when it is signed, ensuring authenticity and integrity.

Signature Field creation

Before jumping to the creation options, let’s review the main characteristics of a Signature Field:

Parameters	Descriptions
`width`	Width of the Signature Field. Optional. Constraints: • The default value is 85px. • 85px is the minimum authorized. • 2000px is the maximum authorized.
`height`	Height of the Signature Field. Optional. Constraints: • The default value is 37px. • 37px is the minimum value authorized. • 1000px is the maximum value authorized.

Signature Field creation with Smart Anchors

To create a Signature Field using Smart Anchors, all you have to do is to add this tag to your document:

Pattern: {{signer_index|signature|width|height}}
Example: {{s1|signature|85|37}}

The Signers index (s1, s2, s3, etc) is determined by the Signers order in the Signature Request. If the index references a non-existent Signer, the Field won’t be created.

Defining X/Y coordinates and a page index is unnecessary when using Smart Anchors, as the Anchor location automatically determines the Field's placement within the Document.

Signature Field creation with API endpoints

To create a Signature Field using the API endpoints, you have two options:

Create a Signer and a Signature Fields at the same time using this endpoint: /POST /signature_requests/{signatureRequestId}/signers
Add a Signature Field to an existing Signer using this endpoint: /POST /fields/{signatureRequestId}/documents/{documentId}/fields

Customisation

Signature reason

The Signature Reason is a value attached to the Signature Field providing context for why the document is being signed.

It is stored in the audit trail and is included in the signature certificate, ensuring traceability and compliance. If no value is specified, the Signature reason will take the default value.

Option chosen	Signature Reason value
Default value	If no custom value is specified, the Signature Reason defaults to: "Signed by [Signer first name] [Signer last name]".
Custom value	You can customize the Signature Reason by specifying the value of the `reason` parameter in the Signature Field creation payload.

Guidelines for Custom Reasons:

Compatibility with signature levels: custom Signature Reasons are only supported for Simple Electronic Signatures (SES). They are not supported for Advanced Electronic Signatures (AES) or Qualified Electronic Signatures (QES).
Length limit: the Signature Reason must not exceed 150 characters.
Content Restrictions: the Signature Reasons cannot include email addresses, links, or HTML tags.

Signature appearance

Signers can choose from three signature design options:

Predesigned signature: this is the default option and the content of the signature will be pre-filled with the Signer name to ease the user experience.
Drawn signature: the Signer can draw their signature.
Signature image upload: the Signer can upload an image of their signature.

Here is an example of the signing page, with those 3 options activated.

If you wish to enable or restrict signature design options available to Signers, you can configure this in the Signature Settings page of your Yousign App.

Once you have changed the configuration, the setting will be applied to all Signature Requests that have not yet been signed.