How does Time-based One-Time Password (TOTP) work?

TOTP (RFC 6238) calculates a 6-digit verification code by computing an HMAC-SHA1 signature using a shared Base32 secret and the current 30-second Unix time epoch interval.

Is this compatible with Google Authenticator, Authy, and 1Password?

Yes, the generated secret keys and otpauth:// URIs follow the open standard supported by Google Authenticator, Microsoft Authenticator, 1Password, and Bitwarden.

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Cryptography

2FA / TOTP Authenticator Generator

Generate RFC 6238 TOTP security codes, base32 secrets, and otpauth:// QR URIs.

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How to Use 2FA / TOTP Authenticator Generator

Use the generated Base32 secret key or paste your existing 2FA secret.
Optionally customize your Issuer Name and Account Email.
Watch the live 6-digit authentication code update every 30 seconds.
Click the Copy button to quickly copy the current 6-digit security code.

Frequently Asked Questions

How does Time-based One-Time Password (TOTP) work?: TOTP (RFC 6238) calculates a 6-digit verification code by computing an HMAC-SHA1 signature using a shared Base32 secret and the current 30-second Unix time epoch interval.
Is this compatible with Google Authenticator, Authy, and 1Password?: Yes, the generated secret keys and otpauth:// URIs follow the open standard supported by Google Authenticator, Microsoft Authenticator, 1Password, and Bitwarden.

Sources & References

Primary references: RFC 6238: TOTP: Time-Based One-Time Password Algorithm; W3C Web Cryptography API.

Review policy: references and behavior notes are checked whenever the tool implementation changes.