Why use HMAC Checker?
HMAC is the backbone of webhook authenticity. Recompute digests with your secret and canonical string to verify implementations across languages and frameworks, especially after SDK upgrades that tweak encoding.
Practical tips
- Confirm whether the provider uses hex versus base64 digests.
- Include or exclude headers exactly as documented—order matters in some schemes.
- Cross-check with Signature Validator presets when available.
Common questions
- Which hash function?
- SHA-256 is most common for webhooks; the tool highlights the selected algorithm.
- Constant-time comparison?
- Use crypto libraries in production servers; browsers are for debugging only.