TOTP Authenticator Ring

Every "Google Authenticator" code on Earth comes from the same 1970s-simple idea: hash a shared secret together with the current time step, then keep six digits of the result. This simulator runs that algorithm for real — genuine HMAC-SHA-1 through the browser's Web Crypto API, dynamic truncation exactly as specified in RFC 6238 — against any Base32 secret you type in. A 3D clock ring ticks once per second of the current time window, a pointer sweeps a full lap every period, and the moment the counter T increments, a fresh code is generated and the key icosahedron flashes. Drag the period, code-length and time-acceleration sliders to see how each term in the formula changes what lands on the ring.