Microdeck.tools 100% In-Browser

Offline Zero-Log JWT & Hash Inspector

100% Private

Inspect JWT headers, claims payloads, and expiration dates locally in your browser memory. Guaranteed zero server transmission or logging.

100% In-Browser No Server Storage Instant Results
100% Offline (Decoded in Browser RAM)
Expires: 9/21/2030, 4:37:02 PM(Issued: 1/18/2018, 1:30:22 AM)
Time Claim Active (Signature Unverified)
Security Notice: Header and payload claims are decoded offline from base64url. Microdeck does not verify cryptographic signatures (HS256) or validate secret keys. Do not rely on unverified claims for authorization without backend cryptographic validation.
Decoded Header (Algorithm & Token Type)
{
  "alg": "HS256",
  "typ": "JWT"
}
Decoded Payload (Claims & Identity)
{
  "sub": "1234567890",
  "name": "Alex Dev",
  "role": "admin",
  "iat": 1516239022,
  "exp": 1916239022
}
Raw Cryptographic Signature (HS256)32 bytes (43 base64url chars)

4z7kM1sK_xW9VbI7p8qT0zJ6mN3rS1tY9uL2vP4wQ5E

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How It Works Under the Hood

Performs base64url decoding entirely inside the browser JavaScript runtime without network calls, keeping sensitive auth tokens confidential.

Step-by-Step Instructions

1

Paste your encoded JWT string.

2

Inspect the color-coded Header (algorithm) and Payload (claims).

3

Verify expiration timestamp and active validity status.

Key Features & Performance

  • Absolute privacy: tokens never touch any server
  • Automatic expiration countdown and active token status indicator
  • Formatted JSON output with 1-click copy

Local Browser Processing & Privacy

Traditional web converters upload your documents, snippets, or media files to remote servers. Offline Zero-Log JWT & Hash Inspector runs inside your browser tab:

Processed in This Tab

Your input text and files are processed locally without uploading payloads to a processing server.

No Tool Payload Logging

Microdeck does not log or store the files or inputs you paste into tool workspaces (normal static hosting/CDN requests still load page assets).

Tab Memory Lifecycle

Working outputs stay in your browser tab and are released when you reset the tool or close the tab.

Frequently Asked Questions

Is it safe to paste production JWT tokens here?

Yes! Microdeck has no backend servers. All processing executes in your local browser sandbox.

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