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Utilnivo

Developer workflow

Debug a JWT or API token

OAuth and API gateways return bearer tokens that are easy to misread in logs. This workflow decodes the JWT structure, formats nested JSON for review, and uses Base64 utilities when you need to inspect individual segments—without installing CLI tools.

Decode a bearer token, pretty-print JSON claims, and inspect Base64 segments.

  • 3 steps
  • About 6 minutes
  • Data stays on this device
  • Updated 2026-07-24
Copy & customize

Workflow

Steps to complete

Work through each step in order. Progress is saved in this browser. Utilnivo does not save uploaded files permanently between tools.

Progress: 0 of 3 steps complete (0%)

  1. Decode JWT

    JWT Decoder

    Inspect header and payload JSON, including exp and iat timestamps.

    • On your device
    • No signup
    Open JWT Decoder

  2. Format JSON

    JSON Formatter

    Pretty-print nested claim objects copied from the payload.

    • On your device
    • No signup
    Open JSON Formatter

  3. Decode Base64

    Base64 Encoder & Decoder

    Inspect individual segments or nested Base64-encoded claim values.

    • On your device
    • No signup
    Open Base64 Encoder & Decoder

Track progress

Your progress

0 of 3 complete (0%). Your progress is saved in this browser.

Printable step list with checkboxes—generated on your device.

Results

Overall output

What you entered and what each step produced appear here. Values used in the next step are passed when supported. Data stays in this browser only.

Run each step and submit the calculator form. Key results will appear here as a connected summary.

Progress: 0 of 3 steps marked complete (0%).

When to use this workflow

  • A login flow returns a token and you need to verify claims.
  • exp, iat, or custom roles look wrong in application logs.
  • You are comparing test tokens across environments.
  • You need to decode a nested claim encoded as Base64.

Tips

Tips for better results

  • Never paste production secrets on shared screens or into untrusted sites.
  • JWT Decoder shows payload but does not verify signatures—verification belongs in your backend.
  • Treat decoded tokens as sensitive; payloads are only encoded, not encrypted.

FAQ

Frequently asked questions

Does this verify the signature?

No. JWT Decoder displays structure for debugging. Signature verification requires your app’s keys and algorithms.

Is my token sent to a server?

Decoding and formatting run on your device. Utilnivo does not store pasted tokens.

Which algorithms are supported?

See JWT Decoder for supported alg values such as HS256 and RS256. Unsupported algs may still decode payload segments.

Keep going

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