Moon Phase Calculator
Determine the exact lunar phase, illumination percentage, and upcoming full/new moon dates for any day.
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Lunar Age: -- days
Illumination
0%
Upcoming Lunar Milestones
Next Full Moon
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Next New Moon
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Synodic Cycle Progress
0%
of 29.53 Day Cycle
Lunar Phase Trend
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About Moon Phases & Lunar Cycles
The Moon Phase Calculator determines the astronomical phase and illuminated surface percentage of the Moon relative to Earth's vantage point on any given date.
The 8 Primary Lunar Phases
- New Moon: The Moon is positioned between Earth and the Sun; illuminated side faces away from Earth (0% illumination).
- Waxing Crescent: A sliver of light appears on the right edge as illumination grows (1%–49%).
- First Quarter: Exactly half of the moon is lit on the right side (50% illumination).
- Waxing Gibbous: More than half illuminated and continuing to brighten (51%–99%).
- Full Moon: Fully illuminated surface directly facing Earth (100% illumination).
- Waning Gibbous: Light begins to decrease from right to left (99%–51%).
- Third Quarter: Exactly half of the moon is lit on the left side (50% illumination).
- Waning Crescent: A final crescent on the left edge before disappearing into the New Moon (49%–1%).