Blue Hour Calculator
Find blue hour times when the sky turns deep blue just before sunrise and after sunset.
How It Works
Blue hour occurs when the sun is between 4 and 8 degrees below the horizon. The sky takes on a rich blue tone. Enter your location to find the morning and evening blue hour windows.
Formula
Blue Hour: sun between -4deg and -8deg below horizon (civil twilight zone)
Frequently Asked Questions
What is blue hour?
Blue hour is the twilight period when the sun is just below the horizon. Indirect sunlight is scattered by the atmosphere creating a vivid blue sky, perfect for photography.
How long is blue hour?
Blue hour typically lasts 20-40 minutes. It occurs twice daily: in the morning before civil dawn and in the evening after civil dusk.