Planetary Hours Calculator
Find the current planetary hour for your location, based on local sunrise and sunset and the Chaldean order of the seven classical planets.
Understanding Planetary Hours
What Are Planetary Hours?
Planetary hours are an ancient timekeeping scheme from Hellenistic astrology, long before mechanical clocks. Instead of 60-minute hours, daylight and night are each divided into 12 unequal segments based on the actual time between sunrise and sunset at your location and date.
That is why planetary hours in New York differ from those in Los Angeles or London on the same day. The order of the planets is the same everywhere, but the clock times depend on your latitude, longitude, and the season.
How to Calculate Planetary Hours
Find your local sunrise and sunset, divide daylight into 12 equal day hours, and divide the time from sunset to the next sunrise into 12 equal night hours. Planets are assigned in the Chaldean sequence: Saturn, Jupiter, Mars, Sun, Venus, Mercury, Moon, repeating.
The planet that rules the first hour after sunrise is the ruler of that day: Sunday belongs to the Sun, Monday to the Moon, Tuesday to Mars, Wednesday to Mercury, Thursday to Jupiter, Friday to Venus, Saturday to Saturn.
Best Activities for Each Planetary Hour
Planetary Hours by City
Planetary hours are location-specific. Choose a city to load its coordinates and recalculate the schedule.
Frequently Asked Questions
The History of Planetary Hours
The scheme comes out of Babylonian and Greek astronomy and was developed by Hellenistic astrologers. The Chaldean order ranks the classical planets from the slowest apparent motion (Saturn) to the fastest (the Moon). Planetary hours were used in medieval and Renaissance astrology and magic, and they remain in use in Western astrology and related traditions for timing activities.
Planetary Hours vs. Vedic Hora
The two systems share the same planetary sequence, but they are applied differently. Western planetary hours split day and night into 12 segments each from local sunrise and sunset. Vedic hora works within the Panchang calendar and can bring in further factors such as lunar mansion.
Keep Exploring
Picking a date for something important? Try the best dates finder. Curious about the sky right now? Read about Mercury retrograde in 2026 or how to read a birth chart. You can also get a free personal reading.
Planetary hours are a traditional astrological practice offered for reflection and entertainment. They do not predict events, and nothing here is medical, legal, or financial advice. Sunrise and sunset are calculated with a standard solar formula and are typically within a few minutes of published almanac times; they do not account for local terrain or elevation.