Development

Webhook signature tester

Compute and verify HMAC webhook signatures for GitHub, Stripe, Slack, or a custom scheme — locally, no network.

Payload

Signing secret

Signature to verify (optional)

Local only — the secret and signature never leave your browser or appear in the URL.

Paste a signature above to check it against the expected value.

Signed base string

The exact string that gets signed appears here.

Expected signature

Add a secret to compute the signature.

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