TOTP & HOTP Test Lab
Investigate one-time password implementations with explicit test parameters. Calculate a code from a Base32 secret or otpauth URI and compare a supplied code without logging into a provider or storing an authenticator account.
About OTP labFeatures & how to use
Test TOTP and HOTP codes locally with Base32 secrets or otpauth URIs. Inspect algorithm, time and counter settings without saving credentials.
What it can do
- Calculate RFC 6238 TOTP using SHA-1, SHA-256 or SHA-512 and RFC 4226 HOTP using SHA-1, with six or eight digits.
- Set the Unix timestamp, period or unsigned 64-bit counter. TOTP comparison checks the selected and adjacent time steps.
- Parse otpauth parameters with duplicate detection; URI settings override manual controls and effective settings are shown in the result.
- Secrets stay in volatile memory and are never included in exports. Codes are snapshots, not a continuously updating authenticator vault; no server clock is queried.
How to use it
- Paste a Base32 secret or otpauth URI and select test parameters.
- Optionally supply a code to compare, then calculate locally.
- Inspect effective parameters and clear the input when finished.