When PFX API signing is the right fit
PFX (PKCS#12) signing is ideal when your backend already holds a certificate password and can call a REST API. It works well for automated invoice runs, batch document processing, and integrations where a USB token is not required.
Request shape
Send a base64-encoded PDF, the PFX password, and either an inline PFX or a certificate alias saved in the portal. Optional signature styles control visible placement without hard-coding coordinates in every client.
- Authenticate with Authorization: Bearer dsc_live_…
- Provide exactly one of pfx_base64 or cert_alias
- Use signature_style to apply a named placement from the dashboard
- Receive signed_pdf_base64 plus hash_before and hash_after prefixes
Security notes
Call the API only from trusted servers. Rotate keys if they leak, store PFX passwords in a secrets manager, and rely on portal audit logs for compliance reviews.