HMAC Generator
The signature webhooks are checked against. Give it the payload and the shared secret and it works out the same digest your server should.
Message
Signed exactly as typed, including trailing new lines. A stray line break is the usual reason two sides disagree.
Key and algorithm
The key is written as
Hash
Show the result as
Signature
Type a message and a key.
Check a signature you were sent
A leading sha256= is stripped for you, and the comparison ignores case.