Moon Phase Calculator
Calculate moon phases, illumination percentage, and upcoming lunar events
Select Date
Current Phase
Moon PhaseFirst Quarter
99% illuminated
Lunar Age8.29 days
Days since last new moon
Upcoming Phases
Full Moon2025-01-14
In 6 days
Last Quarter2025-01-21
In 14 days
New Moon2025-01-29
In 21 days
First Quarter2025-02-05
In 29 days
Characteristics
Visibility
Moon is 99% illuminated
Best Viewing
Early evening
Tides
Neap tides (moderate tidal range)
Understanding Moon Phases
The Moon's appearance changes throughout its monthly cycle as it orbits Earth. These changes, called phases, occur because we see different amounts of the Moon's sunlit surface from Earth.
Main Moon Phases
- New Moon: Moon between Earth and Sun, dark side facing Earth
- First Quarter: Right half illuminated from Earth's perspective
- Full Moon: Moon's entire visible surface illuminated
- Last Quarter: Left half illuminated from Earth's perspective
Lunar Effects
- Ocean Tides: Strongest during New and Full Moons
- Night Sky Brightness: Full Moon provides significant illumination
- Best Viewing Times: Varies by phase and location
- Cultural Significance: Important in many calendars and traditions