Dev Utilities

About Dev Utilities

Dev Utilities is a set of small, focused tools for the text and data developers handle every day: formatting and checking JSON and XML, decoding Base64, URLs and JWTs, converting timestamps, generating UUIDs, comparing texts and testing regular expressions. Each tool is one page that does one job, with an explanation of the format it works on.

The tools

  • Binary Translator: Convert binary code to text and text to binary (UTF-8).
  • JSON Formatter: Beautify, pretty print or minify JSON, with error locations.
  • Base64 Decode: Decode or encode Base64 and Base64URL, UTF-8 safe.
  • Text Compare: Diff two texts or files line by line and word by word.
  • Epoch Converter: Current Unix time, and timestamps to dates and back.
  • JSON Viewer: Explore JSON as a collapsible tree and copy JSONPath.
  • JSON Validator: Lint JSON and see the exact line and column of errors.
  • URL Decoder: Decode or encode percent-encoded URLs and parse query strings.
  • UUID Generator: Generate random UUID v4 (or v7) in bulk and validate UUIDs.
  • XML Formatter: Beautify or minify XML and find well-formedness errors.
  • JWT Decoder: Decode a JWT header and payload and check exp, iat and nbf.
  • Regex Tester: Test JavaScript regular expressions with live highlighting.

Your data stays in your browser

Every tool runs as JavaScript on your own device. The JSON, tokens, files and text you paste or open are processed in the page and are never sent to a server, stored or logged. There are no accounts and no server-side processing; once a page has loaded, the tools keep working even if you go offline. Regular expressions run in a background worker so a slow pattern cannot freeze the page. Random values for UUIDs come from the browser's Web Crypto API.

Even so, treat production secrets such as live access tokens, API keys and passwords with care, and avoid pasting them into any website. See the privacy policy for how advertising and cookies work on this site.

Specifications we follow

The tools implement the published standards for each format rather than one program's behaviour, and each page links the relevant section where it explains a rule:

Where a standard allows several behaviours, the pages say which one the tool uses: for example, the epoch converter detects seconds or milliseconds by size, the URL decoder lets you choose whether + means a space, and the regex tester uses the JavaScript flavour of regular expressions.

Accuracy and feedback

The tools are tested against the examples in these specifications, but no tool is perfect. If you find a result that looks wrong, write to contact.devinventory@gmail.com with the input (or a harmless version of it) and what you expected.