Daylight Length Calculator
Calculate day length, daylight changes, sunrise/sunset context and annual daylight patterns for a selected location.
| Month | First day | Average | End of month | Monthly change |
|---|---|---|---|---|
| Jan | 9 h 18 min | 9 h 38 min | 10 h 04 min | +46 min |
| Feb | 10 h 06 min | 10 h 39 min | 11 h 13 min | +67 min |
| Mar | 11 h 16 min | 11 h 56 min | 12 h 37 min | +81 min |
| Apr | 12 h 40 min | 13 h 18 min | 13 h 54 min | +74 min |
| May | 13 h 56 min | 14 h 27 min | 14 h 52 min | +56 min |
| Jun | 14 h 53 min | 15 h 02 min | 15 h 03 min | +10 min |
| Jul | 15 h 02 min | 14 h 45 min | 14 h 21 min | -41 min |
| Aug | 14 h 19 min | 13 h 45 min | 13 h 08 min | -71 min |
| Sep | 13 h 06 min | 12 h 28 min | 11 h 49 min | -77 min |
| Oct | 11 h 46 min | 11 h 07 min | 10 h 29 min | -77 min |
| Nov | 10 h 26 min | 9 h 56 min | 9 h 30 min | -57 min |
| Dec | 9 h 28 min | 9 h 18 min | 9 h 18 min | -11 min |
Hours of daylight by date
Daylight-length intent is about how many hours of daylight a place gets on a selected date, plus how that changes across the year.
L is daylight length, computed as the local interval between sunrise and sunset when both events occur.
Annual daylight pattern
- Day length changes most quickly around equinoxes.
- The longest and shortest daylight dates occur near local solstices.
- High-latitude locations can have 24-hour daylight or no ordinary sunrise/sunset.
- City search uses geocoding, while the solar calculation uses coordinates and date.
Frequently Asked Questions
Sources and References
- NOAA Solar CalculatorNOAA Global Monitoring Laboratory
- Sunrise and Sunset Calculatortimeanddate.com
- Open-Meteo Geocoding APIOpen-Meteo
- DateMDN Web Docs
Calculations are based on the listed reference sources. Links open in a new tab.
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