Tools
Planetary hours calculator: today’s day and night hours
Planetary hours divide the time from sunrise to sunset into twelve parts and the following night into another twelve. Their duration therefore depends on the date and location. Each interval receives a ruler according to a traditional astrological convention.
Updated October 25, 2026
Try the tool
Context and method
Sunrise and sunset are astronomical calculations. The sequence of rulers — Saturn, Jupiter, Mars, Sun, Venus, Mercury and Moon — belongs to the tradition. The tool keeps these two layers distinct.
How to study and use it
Choose a city or enter coordinates and a date. Check the displayed time zone, then read the daytime and nighttime intervals. Before sunrise, the current planetary hour belongs to the preceding planetary day’s night.
Important distinctions
A planetary hour does not always last sixty minutes. Where a date has no sunrise or sunset, the traditional division cannot be constructed in the same way. The calculator reports missing events instead of inventing times.
Frequently asked questions
Does a planetary hour last sixty minutes?
Not necessarily. Sunrise to sunset and the following night are each divided into twelve parts. Their lengths vary with the date and location.
Which hour applies before sunrise?
The current hour belongs to the previous planetary day’s night. The calculator identifies that interval when you view today.
What if there is no sunrise or sunset?
A planetary hour does not always last sixty minutes. Where a date has no sunrise or sunset, the traditional division cannot be constructed in the same way. The calculator reports missing events instead of inventing times.
Sources and further reading
Related reading
Check the language, author and edition in the catalogue. Titles below retain their recorded spelling.
- A Cabala da Astrologia — William Eisen
- A Nova Astrologia — Suzanne White
- A Ciência da Astrologia — Ricardo Lindemann
- A Astrologia do Karma — Pauline Stone
- A Astrologia e a Arte de Curar — A. T. Mann
- Astrologia Cármica - Roda da Fortuna — Martin Schulman