Create or verify HMAC signatures for generic webhooks, GitHub X-Hub-Signature-256, and Stripe-style v1 signatures.
Enter a secret and payload to generate a signature.
Generate a signature to see the corresponding request header.
Generate a signature to see Node.js and PHP verification patterns.
Webhook checks fail when middleware parses or reformats the body before verification. Keep the raw body, apply the provider's documented signing input, and use a timing-safe comparison in your server code. This page never sends the payload or secret anywhere.