TOTP / HOTP Authenticator
Generates time-based (TOTP) and counter-based (HOTP) one-time passwords from a Base32 secret — the same 6-digit codes Google Authenticator and Authy produce — shows the live code with its countdown, and builds the otpauth:// URI you can turn into a QR code.
Runs 100% in your browser — keys and data never leave your device.
Read the full guide to this tool
Notes
- TOTP is HOTP with the counter set to the current 30-second time step (RFC 6238), so codes rotate on a shared clock without any network round-trip.
- The shared secret is the crown jewel: anyone with it can generate valid codes forever. It stays in your browser here.
- Runs 100% in your browser — keys and data never leave your device.
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