b2KIT

Two-Factor Auth Tester

Generate TOTP codes from a secret key (RFC 6238). Verify codes and test your 2FA setup in real time.

Test with: JBSWY3DPEHPK3PXP (common test secret)

How TOTP Works
  • Uses HMAC-SHA1 with a shared secret key
  • Time-based counter changes every 30 seconds
  • Produces a 6-digit code (RFC 6238)
  • Same algorithm used by Google Authenticator, Authy, etc.
  • All computation happens locally in your browser

How to Use Two-Factor Auth Tester

  1. 1

    Enter a secret key

    Paste the TOTP secret key or scan a QR code.

  2. 2

    Generate a code

    See the current time-based one-time password generated.

  3. 3

    Verify the code

    Test that the generated code matches your authenticator app.

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