OTPClient is GTK+ software for two-factor authentication that supports both Time-based One-time Passwords (TOTP) and HMAC-Based One-Time Passwords (HOTP).

Features: - Support both TOTP and HOTP. - Support setting custom digits (between 4 and 10 inclusive). - Support setting a custom period (between 10 and 120 seconds inclusive). - Support SHA1, SHA256 and SHA512 algorithms. - Support for Steam codes. - Import encrypted Authenticator Plus backup. - Import and export encrypted and/or plain andOTP backup. - Import and export plain FreeOTPPlus backup (key URI format only). - Import and export plain Aegis backup (plain json only). - Local database is encrypted using AES256-GCM. * Key is derived using PBKDF2 with SHA512 and 100k iterations. * Decrypted file is never saved (and hopefully never swapped) to disk. While the app is running, the decrypted content resides in a "secure memory" buffer allocated by Gcrypt.