Stacked 24-hour day/night bars for multiple time zones, centred on your current time.
- Bars are shaded by the sun's real elevation at each zone's reference city (day, civil / nautical / astronomical twilight, night).
- Local times come from the browser's time zone database, so DST and half-hour offsets are handled, including a DST change inside the 24-hour window.
- Hover or drag across the bars to read every zone's time at that moment.
- The address bar always holds the current list (
?z=Europe/London,Pacific/Auckland), so it can be bookmarked or shared. Opening someone else's link shows their list without replacing your saved one. - Installable as a PWA and works offline once loaded (
manifest.webmanifest,sw.js).
Plain static HTML/JS, no build step. Pushing to main deploys via .github/workflows/pages.yml, which stamps the commit SHA onto the script URLs to bust browser caches.
Zone coordinates in zones.js are generated from tzdata's zone.tab:
python3 scripts/build_zones.py /usr/share/zoneinfo/zone.tabApp icons in icons/ are drawn by python3 scripts/build_icons.py.