Day Length Calculator
Daylight Length Across the Year
Day length is the time between sunrise and sunset. It varies across the year — most dramatically at high latitudes, least at the equator. This tool computes day length for every day of a chosen year and highlights the longest (June solstice in the Northern Hemisphere, December in the Southern) and shortest days.
The sun graph has two views. Day/Night Length stacks night, twilight, and daylight durations so you can see how the daylight envelope grows and shrinks across the year. Rise/Set Times plots the same data by local clock hour, showing sunrise, sunset, twilight bands, and solar noon. Dotted markers sit on each solstice and equinox.
Polar locations show flat stretches at 0h (polar night) and 24h (midnight sun) during the months the sun never crosses the horizon.