How to Use the Blue Hour Time Calculator
Blue hour is the brief window right after sunset when the sky turns a deep, saturated blue — a favorite for cityscape and portrait photography. Missing the exact window makes it hard to capture that color, so it helps to calculate the timing ahead of time. This calculator takes your sunset time and the latitude of your shooting location and estimates when blue hour starts and ends.
Blue hour largely overlaps with civil twilight, the period after the sun has fully dropped below the horizon when only scattered atmospheric light keeps the sky blue rather than dark. It typically begins about 10 minutes after sunset, and at higher latitudes, the sun sets at a shallower angle, which stretches out both the twilight period and blue hour itself.
Actual color and duration can shift a bit with season, weather, and atmospheric conditions, so it's a good idea to arrive at your location early and set up your composition ahead of the calculated window.
Frequently Asked Questions
Golden hour is when the sun sits low near the horizon, casting warm-toned light. Blue hour is the short window after the sun fully sets, when scattered light in the sky turns blue — it usually follows right after golden hour.
At higher latitudes, the sun sets at a shallower angle relative to the horizon, which stretches out the twilight period and makes blue hour last longer.