Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
TOTP Authenticator Generator
Generate TOTP secrets and QR codes compatible with Google Authenticator, Authy, and other authenticator apps.
- Home
- Hash & Security
- TOTP Authenticator Generator
Click Generate
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How to Use
- Enter the issuer name (e.g., "GitHub") and your account name (e.g., your email)
- Click Generate New Secret to create a random TOTP secret and QR code
- Scan the QR code with Google Authenticator, Authy, 1Password, or any TOTP-compatible authenticator app
- The generated TOTP code updates in real-time — verify it matches your authenticator app
What is TOTP?
TOTP (Time-based One-Time Password) is an algorithm defined in RFC 6238 that generates one-time passwords using a shared secret key and the current time. It is widely used for two-factor authentication (2FA).
Key Parameters
- Secret — A Base32-encoded shared key (typically 160 bits/32 chars)
- Time step — The interval between code changes (usually 30 seconds)
- Digits — The length of the generated code (usually 6 digits)
- Algorithm — The HMAC hash algorithm used (SHA-1 is the most widely compatible)
Frequently Asked Questions
Is this compatible with Google Authenticator?
Yes. The generated secret and QR code follow the otpauth:// URI format (RFC 6238), which is supported by Google Authenticator, Authy, Microsoft Authenticator, 1Password, Bitwarden, and all standards-compliant TOTP apps.
What secret size should I use?
160 bits (32 Base32 characters) is the recommended size, used by Google Authenticator and most services. 128 bits is shorter but still cryptographically secure. 256 bits provides extra security but may not be supported by all authenticator apps.
Does this generate codes server-side?
No. Everything runs locally in your browser using the Web Crypto API. The secret is generated using cryptographically secure random values, and TOTP codes are calculated client-side. Your secret never leaves your device.
Last updated: 17 Aug 2026
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