---
title: SPKI-SHA256-BASE64
framework: bundleresources
role: symbol
role_heading: Property List Key
path: bundleresources/information-property-list/nspinnedleafidentities/spki-sha256-base64
---

# SPKI-SHA256-BASE64

The digest of an X.509 certificate’s Subject Public Key Info structure.

## Discussion

Discussion You represent a pinned certificate using the Base64-encoded SHA-256 digest of an X.509 certificate’s DER-encoded ASN.1 Subject Public Key Info (SPKI) structure. For a PEM-encoded public-key certificate stored in the file ca.pem, you can calculate the SPKI-SHA256-BASE64 value with the following openssl commands: % cat ca.pem |       openssl x509 -inform pem -noout -outform pem -pubkey |       openssl pkey -pubin -inform pem -outform der |       openssl dgst -sha256 -binary |       openssl enc -base64