JWT Signature Verifier
Security ToolsVerify HS256, RS256 and ES256 JWT signatures
FreePrivateInstant
Add a file · .txt .md .csv .json … · up to 2.00 MB
Secret (HS) or public key PEM (RS / ES)
Add a file · .txt .md .csv .json … · up to 2.00 MB
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History
All history →JWT Signature Verifier — at a glance
Verify HS256, RS256 and ES256 JWT signatures.
Your text or values
Run
Instant result
How to use it — step by step
Just your input — nothing to install or sign up for.
1
Add your input
Paste or type into the big box, or press “Try a sample” to see an example.
2
Choose options
Pick the settings you want. The defaults work well for most people.
3
Run the tool
Press the button and the result appears in a moment.
4
Copy the result
Use the Copy button to paste it wherever you need.
Pro tips
Small things that make the result better.
✦Your token and key never leave your browser.
✦A valid signature does not mean the token is still allowed — also check exp, aud and iss on your server.
Quick facts
Freeno signup, no limit
Instantresult in a moment
Privatenothing is uploaded
Any devicephone, tablet or PC
Frequently Asked Questions
Is my data safe?+
Yes. Everything runs inside your own browser. Your text, files and images are never uploaded to any server.
Is this tool really free?+
Yes — completely free, no signup, no watermark and no usage limit.
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