Moon Phase Calculator
Find the lunar phase for any date with a visual moon diagram. See moon age, illumination percentage, phase name and next full and new moon dates.
The Eight Moon Phases
| Phase | Moon Age | Illumination | Description |
|---|---|---|---|
| 🌑 New Moon | 0 days | ~0% | Moon between Earth and Sun |
| 🌒 Waxing Crescent | 1–7 days | 1–49% | Right side growing brighter |
| 🌓 First Quarter | ~7 days | ~50% | Right half illuminated |
| 🌔 Waxing Gibbous | 7–14 days | 51–99% | More than half lit, growing |
| 🌕 Full Moon | ~14 days | ~100% | Moon fully illuminated |
| 🌖 Waning Gibbous | 15–22 days | 51–99% | More than half lit, shrinking |
| 🌗 Last Quarter | ~22 days | ~50% | Left half illuminated |
| 🌘 Waning Crescent | 22–29 days | 1–49% | Left side fading |
The Synodic Month
The Moon takes 29.53059 days to complete a full cycle from new moon to new moon — this is called the synodic month. The calculation uses a known new moon date (January 6, 2000) and counts elapsed synodic periods to determine the current phase for any date.
Moon Phase and Its Cultural Significance
Moon phases have been used to mark time, guide planting, and inform cultural ceremonies for thousands of years. Many religious calendars — including the Islamic Hijri calendar, the Hebrew calendar, and the Hindu Panchang — are based on the lunar cycle. The full moon names (Harvest Moon, Hunter's Moon, Strawberry Moon) originate from Indigenous American and colonial farming traditions, each tied to seasonal activities. Many gardeners still follow moon phase planting guides, sowing root crops during a waning moon and leafy greens during a waxing moon.
Moon Phase and Photography
Knowing the moon phase is essential for planning night photography. A new moon produces the darkest skies — ideal for Milky Way and deep-sky photography. A full moon provides enough ambient light to illuminate landscapes for long-exposure shots and light-painting. The first and last quarter phases offer interesting moonrise and moonset timing for compositional shots. Check the phase for your shoot date and plan accordingly — a full moon on your intended astrophotography night washes out faint stars.