Otemoto Tools by ATI K.K.

🔒 Authentication & Security

• 🔒 TOTP Code Generator

  Computes two-factor authentication (2FA) one-time codes from a Base32 secret or otpauth:// URI. Useful for verifying a 2FA setup or migrating to another authenticator app.

• 🔒 JWT Viewer

  Decodes and displays the header and payload of a JWT (JSON Web Token), converting exp / iat / nbf into readable dates. It does not verify signatures.

• 🔒 Password Generator

  Generates passwords with a cryptographically secure random number generator (CSPRNG). Choose the length (8–128) and character types. Nothing is stored.

• 🔒 SHA-256 / File Hash

  Computes SHA-256 / SHA-384 / SHA-512 hashes of text or files — for example to verify that a downloaded file matches its published checksum.

• 🔒 Secret Masker

  Detects and masks password-, API-key- and token-looking values in logs, config files and error messages — a quick pass before pasting them into an AI chat or a support ticket.

Images

• Image Resize

  Resizes images in your browser and saves them as JPEG / PNG / WebP. Aspect ratio is preserved automatically. Images are never uploaded.

• Make Background / Color Transparent

  Turns a chosen color transparent and saves a transparent PNG. Two modes: remove only the background connected to the edges, or remove every matching color. With tolerance control and an eyedropper.

Data / Utility

• QR Code

  Generates QR codes and saves them as PNG, and reads QR codes from image files. URLs found in a QR code are never opened automatically.

• JSON Formatter

  Pretty-prints, minifies and validates JSON. Syntax errors are reported with line and column numbers.