Date Tools

A lightweight browser app for common date/time tasks:

• Date and time difference (datetime-local to datetime-local)
• Unix timestamp to zoned local time + UTC
• Zoned date/time to Unix seconds + milliseconds

The UI is localized in English, German, and Portuguese based on browser language.

Features

• Runs fully in the browser (no backend required)
• Supports global time zone selection (IANA zones)
• Handles Unix input in seconds or milliseconds
• Includes responsive dark UI for desktop and mobile
• Adds SEO and social metadata for deployment as a public utility page

Files

• date.html - Main page markup, styles, and script includes
• date.js - Readable source JavaScript (i18n, date math, timezone picker, conversions)
• date.min.js - Minified JavaScript loaded by date.html

Run Locally

No build step is required.

1. Open date.html directly in your browser, or
2. Serve the folder with a static server:

python3 -m http.server 8000

Then open http://localhost:8000/date.html.

Dependencies

• Luxon is loaded from jsDelivr in date.html and is used for time zone aware datetime-local to Unix conversion.

If Luxon fails to load, local-zone conversion still works, while explicit non-local zone conversion shows an in-app error message.

Build date.min.js

To regenerate the minified bundle from date.js, use Terser:

npx terser date.js --compress --mangle --output date.min.js

Optional check (shows output size):

ls -lh date.min.js

Notes

• date.html currently references date.min.js.
• If you edit date.js, regenerate date.min.js before deploying so both stay in sync.