0 chars0 bytes
Computed Digest
Hex Output
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Base64 Output
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Integration Tip (Node.js)
crypto.createHmac('sha256', secret).update(payload).digest('hex')
HMAC Webhook Generator (Offline & Secure)
Free online HMAC generator — compute SHA-256 and SHA-512 HMAC signatures in Hex and Base64 for Stripe and GitHub webhook testing. 100% client-side.
How to use HMAC Generator
- Enter your secret key in the Secret field.
- Paste your payload data into the Payload field.
- Select your hashing algorithm (SHA256 or SHA512).
- Instantly view and copy the generated Hex and Base64 signatures.
Edge Cases & Important Considerations
- Very large payloads may cause a brief browser hang during cryptographic calculation.
Keyboard Shortcuts
- Ctrl/Cmd + K — Open Command Palette to switch tools instantly.
Frequently Asked Questions
Is this HMAC Generator safe for sensitive corporate data?
Yes, 100%. All processing runs client-side in your local browser memory. No text, tokens, payloads, or logs are ever transmitted to any remote server or analytics engine.
Can I use this tool offline?
Yes. Because this tool runs strictly on client-side JavaScript with zero external API dependencies, once loaded it functions completely offline.
100% Client-Side Privacy Guarantee
All inputs are processed entirely inside your browser's memory using JavaScript. No data is ever transmitted to any server. Your tokens, JSON payloads, cURL commands, and timestamps never leave your machine.