Online tools for developers

Everyday utilities, ready when you open the page. Tool inputs are processed locally in your browser.

• JSON Formatter & Validator

  Format, minify, validate, and sort JSON with precise errors and lossless large-integer handling.

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• Timestamp Converter

  Convert Unix timestamps to human-readable dates and back, with seconds/milliseconds and time zone support.

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• Base64 Encoder & Decoder

  Strictly encode and decode UTF-8 text with explicit Base64 or Base64URL alphabets and padding.

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• URL Encoder, Decoder & Parser

  Encode or decode URL text instantly, with optional full-URL and form handling, and parse URLs with the WHATWG standard.

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• JWT Decoder

  Decode JWT headers, payloads, and standard claims, inspect expiration, and recognize five-part JWE locally.

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• JSON to TypeScript

  Conservatively convert JSON to TypeScript interfaces or types with safe optional fields, unions, and unknowns.

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• JavaScript Playground

  Write and run JavaScript snippets right in your browser and see the output instantly.

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• Excel to JSON Converter

  Convert Excel spreadsheets to JSON and back, entirely in your browser — no upload.

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• JSON Masker

  Mask sensitive field values in JSON with one click so you can share API data safely.

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