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OTP Code Generator

Used by developers, writers, and creators worldwide.

An OTP code generator is the fastest way to get realistic one-time passcodes for testing auth flows, populating UI mockups, and seeding QA fixtures — without triggering a real SMS gateway or TOTP library. Developers building two-factor authentication screens, designers mocking up verification flows in Figma, and QA engineers writing Cypress login tests all need codes that look real without being real. This tool generates batches of random numeric OTPs instantly. Set the digit length to 4, 6, or 8 to match your system, add a dash or space separator to replicate how your app displays codes, and adjust the count to however many you need.

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Free forever — no account required

How to use

  1. Choose your options above
  2. Click Generate
  3. Copy your result

Detailed instructions

  1. Set the OTP Length input to 4, 6, or 8 digits to match your target authentication system's format.
  2. Enter the number of codes you need in the 'How many OTPs' field — use a higher count for batch testing.
  3. Choose a Group Separator if your UI displays codes with spaces or dashes between digit groups.
  4. Click Generate to produce your list of OTP codes instantly in the output panel.
  5. Copy the full list or individual codes into your test suite, prototype, or documentation as needed.

Use Cases

  • •Populating Figma login screens with formatted 6-digit OTPs that match production display
  • •Seeding a Jest or Cypress fixture file with 50 mock verification codes for auth flow tests
  • •Load-testing an OTP validation endpoint in Postman without triggering real Twilio SMS sends
  • •Generating dash-separated 8-digit codes to match hardware token format in developer docs
  • •Creating realistic screenshot content for App Store previews showing an SMS verification screen

Tips

  • →Match the digit count to your real system first — mixing 6-digit mock codes with a 4-digit input field breaks UI testing.
  • →Use the space separator when creating screenshots for app store listings; it matches how iOS and Android native OTP fields display codes.
  • →Generate 20+ codes at once for load testing so each simulated request gets a unique mock value without repeating.
  • →Paste the output into a Postman environment variable list to cycle through different OTP values across multiple test runs.
  • →If your UI truncates long codes, test with 8-digit codes to catch overflow or ellipsis bugs early in design review.
  • →Combine this with a mock SMS template to create fully realistic end-to-end demo screenshots without a live backend.

FAQ

how to generate fake otp codes for testing without using a real sms service

Use this tool to produce as many random numeric codes as you need, then paste them directly into your test fixtures, Postman collection, or seed script. Because the codes are generated client-side, no SMS gateway is contacted and no rate limits apply. For algorithmically correct TOTP codes tied to a secret, use a library like speakeasy (Node) or pyotp (Python) instead.

are randomly generated otp codes safe to use in development

Yes, for development and prototyping purposes. The codes are produced client-side in your browser and never sent to any server. They are not cryptographically secure — they use JavaScript's Math.random() — so never substitute them for real OTPs in a production authentication system.

what's the difference between a 4-digit pin and a 6-digit otp

4-digit PINs are typical for simpler flows like debit card verification or basic app locks. 6-digit codes are the dominant standard for two-factor authentication, used by Google Authenticator, Authy, and most SMS services. 8-digit codes appear in higher-security contexts such as hardware tokens. Match the digit setting here to whatever length your target system expects.