JWT Signer
Encoding & Encryption · Free Online Tool
Sign JWT tokens with HS256/HS384/HS512 (HMAC).
Click "Sign" to generate a JWT...HMAC Algorithms
Sign with HS256, HS384 or HS512 — symmetric signing with a shared secret.
Web Crypto Native
All HMAC operations use crypto.subtle — audited and hardware-accelerated.
Base64URL Output
Header and payload are base64url-encoded and joined into a standard three-part token.
How to Use JWT Signer
- 1Enter or paste your data into the input field.
- 2Select the desired encoding, hashing, or encryption options.
- 3Click the action button to process your data.
- 4Copy the result from the output field.
Features
- ✓100% free — no signup, no subscription, no ads
- ✓Runs entirely in your browser — data never leaves your device
- ✓Fast and lightweight — instant results
- ✓Cross-platform — works on desktop, tablet, and mobile
Frequently Asked Questions
Is my data safe?
Yes. All encoding, hashing, and encryption operations run entirely in your browser. Your data is never sent to any server.
Can I use this for passwords?
We recommend using the Password Generator for creating secure passwords, and Bcrypt Hash for storing password hashes. Never store plain-text passwords.
What hash algorithms are supported?
The Hash Generator supports MD5, SHA-1, SHA-256, and SHA-512. For HMAC signatures, use the HMAC Generator.
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Learn the concept
Learn the concept
Understand the programming ideas behind this tool.