TOTP Authenticator & 2FA Code Generator: What It Does
Generates RFC 6238 Time-based One-Time Passwords (TOTP) from Base32 secret keys. It shows real-time countdown progress, verifies authentication codes, and renders otpauth QR codes for mobile authenticators.
Example
JBSWY3DPEHPK3PXP6-digit code (e.g. 284915) with 30s countdownComputes HMAC-SHA1 over current 30-second Unix time intervals.
How to Use
- Paste a Base32 secret key into the input field.
- Inspect the live 6-digit one-time code and progress timer.
- Scan the generated QR code with authenticator apps like Google Authenticator or 1Password.
Limitations
- System clock drift exceeding 30 seconds can cause codes to fail verification on remote servers.
- Standard authenticators use 30-second periods; non-standard interval keys must be configured manually.
Frequently Asked Questions
How does TOTP keep codes synchronized without communicating with a server?
Both the authenticator and server derive codes from the shared secret and current Unix timestamp, divided into identical 30-second intervals.
What algorithm do most two-factor authenticator apps use?
Most services implement RFC 6238 using HMAC-SHA1 with a 30-second step interval and 6-digit truncation.
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