Planetary Hours

Planetary Hours calculates the ancient system of planetary hours for any location on Earth. Each day is divided into planetary hours — variable-length time segments ruled by the seven classical planets in the traditional Chaldean order: Saturn, Jupiter, Mars, Sun, Venus, Mercury, and Moon.

Unlike clock hours, planetary hours divide the period from sunrise to sunset into 12 equal day hours, and sunset to the next sunrise into 12 equal night hours. Their length changes with the seasons, giving you a living rhythm tied to actual daylight at your location.

USE PLANETARY HOURS FOR
• Electional astrology — choose the right time to start important activities
• Spiritual and ritual practice — align your work with planetary energies
• Daily planning — structure your day using traditional timing
• Meditation and mindfulness — attune to natural cycles

FEATURES
• Accurate planetary hour calculations based on precise sunrise and sunset data
• Search and select any city worldwide with automatic timezone detection
• Navigate between dates with a calendar picker or keyboard shortcuts
• View planet names or traditional astrological glyphs
• Colour-coded planetary hours using traditional associations
• Switch between 12-hour and 24-hour time formats
• Progress indicators showing time remaining in the current hour
• Export your planetary hours schedule to your calendar (.ics)
• Copy the full schedule to your clipboard
• Auto-updating display that tracks the current hour in real time
• Light and dark themes with an optional animated starfield background
• Dynamic app icon colour matching the current ruling planet

LUNAR EVENTS
• Current moon phase, lunar age, and zodiacal sign
• Upcoming new moons, full moons, and eclipses
• Optional quarter phase display

NOTIFICATIONS
• Set alerts for specific planetary hours
• Customise timing — get notified at the event or up to 45 minutes before
• Filter by planet, day or night hours, or specific hour numbers

LEARN
• Built-in guide covering the history and practice of planetary hours
• Origins in Mesopotamian and Babylonian astronomy
• The Chaldean order and how planetary days are named
• How calculations work and how to apply them