Sunrise / Sunset Calculator

Twilight phases explained

• Civil twilight — sun 0 to 6° below horizon. Bright enough to do outdoor activities. Streetlights start turning on.
• Nautical twilight — 6 to 12° below. Horizon still visible at sea (hence the name). The brightest stars become visible.
• Astronomical twilight — 12 to 18° below. Sky appears fully dark to the eye; faint stars and deep-sky objects start being observable.

Use cases

• Photography — "golden hour" = ~1h before sunset / after sunrise. "Blue hour" = civil twilight
• Outdoor activities — when does it get dark enough to need a head torch
• Astronomy — astronomical twilight is when serious observing starts
• Travel planning — daylight hours at your destination during your visit

Privacy

All math runs in your browser. The "My location" button uses your device's geolocation only after you grant permission — the coordinates aren't sent anywhere.