diff --git a/lib/submissions/timestamp_handler.rb b/lib/submissions/timestamp_handler.rb
index da8eb845..9f10064a 100644
--- a/lib/submissions/timestamp_handler.rb
+++ b/lib/submissions/timestamp_handler.rb
@@ -2,7 +2,7 @@
 
 module Submissions
   class TimestampHandler
-    HASH_ALGORITHM = 'SHA512'
+    HASH_ALGORITHM = 'SHA256'
 
     TimestampError = Class.new(StandardError)