TOTP setup QR generator
URI, QR and downloaded files contain the secret: anyone who has them can generate codes. Masked input, no tool storage/network submission. Generated keys:20/32/64bytes for SHA1/256/512. Defaults SHA1/6digits/30seconds; verifier and authenticator must use matching parameters. Client support varies; legacy clients may ignore custom algorithm/digits/period. Optional snapshot is calculated only on Run, not a live authenticator. No account activation, server verification or clock synchronization.