SAML Response Decoder

A simple, client-side tool to decode and inspect SAML responses. All processing happens locally in your browser — no data is sent to any server.

🚀 Live Site

https://samlresponsedecoder.jusuchin85.com

✨ Features

• Decode base64-encoded SAML responses
• View raw decoded XML with one-click copy
• Extract X.509 certificate details (Issuer, Subject, Validity, Signature Algorithm)
• View raw certificate in PEM format
• Display SAML assertion info (NameID, Issuer, Destination, NotBefore, AuthnInstant, NotOnOrAfter, Status)
• Show SAML attributes (displayname, email, etc.)
• Visual indicators for expired/valid timestamps
• Helpful tooltips on hover for all fields
• Dark mode with system preference detection
• 100% client-side — your data never leaves your browser

📖 Usage

1. Paste your base64-encoded SAML response into the text area
2. Click Decode
3. Review the extracted information

🔍 How to Capture a SAML Response

To capture a SAML response from your browser for troubleshooting:

Chrome / Edge

1. Open Developer Tools (F12 or Cmd+Option+I on Mac)
2. Go to the Network tab
3. Check Preserve log
4. Initiate the SAML login flow (e.g., sign in to the app)
5. In the Network tab, look for a POST request to a URL containing /saml/consume or /acs
6. Click on the request, go to the Payload tab
7. Find the SAMLResponse parameter and copy its value

Firefox

1. Open Developer Tools (F12 or Cmd+Option+I on Mac)
2. Go to the Network tab
3. Check Persist Logs
4. Initiate the SAML login flow
5. Look for the POST request to the ACS (Assertion Consumer Service) URL
6. Click on the request, go to the Request tab
7. Find and copy the SAMLResponse value

Using Browser Extensions

You can also use extensions like:

• SAML-tracer (Firefox)
• SAML Chrome Panel (Chrome)

For more details, see Okta's guide on viewing SAML responses.

🔒 Privacy

All decoding happens locally in your browser using JavaScript. No SAML data is transmitted to any external server.

📄 License

MIT