Question 1

Is DevTools360 JWT Decoder free to use?

Accepted Answer

Yes, DevTools360 JWT Decoder is 100% free with no hidden costs, subscriptions, or premium tiers. All JWT decoding and verification features are completely free. We believe powerful developer tools should be accessible to everyone.

Question 2

How do I decode a JWT token?

Accepted Answer

Simply paste your JWT token into DevTools360 JWT Decoder. The tool automatically decodes the token header and payload, displaying them in a readable JSON format. You can also click the "Decode" button or use Ctrl/Cmd+Enter for quick decoding.

Question 3

How do I verify a JWT signature?

Accepted Answer

Select the algorithm used to sign your JWT (HS256, RS256, ES256, etc.), enter the secret key (for HMAC) or public key (for RSA/ECDSA), and click "Verify Signature". The tool will verify the token signature locally in your browser.

Question 4

Is my JWT token data safe and private?

Accepted Answer

Absolutely! DevTools360 processes all JWT tokens locally in your browser. We never upload, store, transmit, or analyze your tokens, secrets, or keys. Your JWT data remains 100% private on your device. This is a privacy-first JWT tool.

Question 5

What JWT algorithms are supported?

Accepted Answer

DevTools360 supports all major JWT algorithms: HS256, HS384, HS512 (HMAC), RS256, RS384, RS512 (RSA), and ES256 (ECDSA). The tool can decode any JWT token and verify signatures using these algorithms.

Question 6

What are JWT claims?

Accepted Answer

JWT claims are pieces of information asserted about a subject. Standard claims include exp (expiration time), iat (issued at), nbf (not before), iss (issuer), sub (subject), and aud (audience). DevTools360 automatically validates time-based claims and shows human-readable timestamps.

Question 7

How do I check if a JWT token is expired?

Accepted Answer

DevTools360 automatically checks the exp (expiration) claim in your JWT token. If the token is expired, it will show "Expired" with how long ago it expired. If valid, it shows "Valid for X" with a countdown.

Question 8

Does DevTools360 work offline?

Accepted Answer

Yes! Once loaded, DevTools360 JWT Decoder works completely offline. All JWT decoding and verification features work without an internet connection. Perfect for developers working in remote locations or with sensitive tokens.

Question 9

Can I verify JWT tokens with RSA public keys?

Accepted Answer

Yes! DevTools360 supports RSA signature verification (RS256, RS384, RS512). Simply paste your RSA public key in PEM format, select the algorithm, and click "Verify Signature". The tool handles all the cryptographic verification locally.

Question 10

Is DevTools360 better than other JWT decoders?

Accepted Answer

DevTools360 is the best free JWT tool because it's privacy-first (zero uploads), supports all major algorithms, validates claims automatically, works offline, and provides real-time decoding. All features are free with no limitations.