OTP Generator creates time-based (TOTP) and HMAC-based (HOTP) one-time passwords following RFC 6238 and RFC 4226 respectively. It supports configurable digit lengths (6 or 8), time steps (30 or 60 seconds), and hash algorithms (SHA-1, SHA-256, SHA-512). The tool displays the current OTP with a countdown timer for TOTP, generates QR codes compatible with authenticator apps like Google Authenticator and Authy, and can verify OTPs against a provided secret for testing.
Security engineers testing 2FA implementations, backend developers building authentication systems, and QA teams validating OTP workflows. The tool runs entirely in your browser — your data never leaves your device.
Learn more about related topics: RFC 6238, TOTP, HOTP, Two-factor authentication.
OTP Generator is a free, browser-based developer tool on AIDToolStack. Generate and validate TOTP one-time passwords with countdown timer. It requires no installation or sign-up and works entirely in your browser.
Yes, completely free. OTP Generator has no usage limits, no account requirements, and no hidden fees. Use it as often as you need.
No, all processing happens locally in your browser. Your data never leaves your device and nothing is sent to any server.
Yes, it works in any modern browser on both desktop and mobile devices. No app download required — just open the page and start using it.
AIDToolStack tools run entirely in your browser with no server processing. This means faster results, complete privacy, and zero downtime. There are no ads blocking your workflow, and everything is free with no sign-up required.
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