Moon Phase Calculator
View the current moon phase with a visual display. Look up moon phases for any past or future date.
Reading the moon phase
The page shows tonight's phase as an image, its name, the percentage of the disc that is lit, the Moon's age in days since the last new moon, and the dates of the next new and full moons. Enter any date, past or future, to see the phase on that day, and browse a full-moon calendar for the year. The calculation uses the standard astronomical algorithm for the Moon's synodic period, and is accurate to within a few hours, which is more than enough for planning; the exact instant of full moon is given in your local time.
The eight phases
| Phase | Days after new moon | What you see (northern hemisphere) |
|---|---|---|
| New moon | 0 | Nothing; the Moon is between Earth and Sun. |
| Waxing crescent | 1–6 | A thin sliver on the right, visible after sunset. |
| First quarter | ~7.4 | Right half lit; rises at noon, sets at midnight. |
| Waxing gibbous | 8–13 | More than half lit, growing. |
| Full moon | ~14.8 | Fully lit; rises at sunset, up all night. |
| Waning gibbous | 16–21 | Shrinking from the right. |
| Last quarter | ~22.1 | Left half lit; rises at midnight. |
| Waning crescent | 23–29 | A sliver on the left, visible before dawn. |
In the southern hemisphere the lit side is mirrored: the crescent grows from the left. A full cycle (synodic month) averages 29.53 days, which is why full moons drift through the calendar and why a month occasionally has two ("blue moon").
Why people check it
- Stargazing and astrophotography. Faint objects and the Milky Way need a dark sky: plan for the week around new moon. The Moon itself photographs best near first or last quarter, when the terminator casts long shadows across craters.
- Night hikes and camping. A full moon gives enough light to walk without a torch; a new moon gives the best view of the stars.
- Fishing and tides. Spring tides (the largest range) occur at new and full moon; neap tides at the quarters.
- Religious calendars. Islamic months begin with the sighting of the new crescent; Easter falls on the first Sunday after the first full moon on or after the spring equinox; many East Asian festivals follow the lunar calendar.
- Gardening by the moon is a tradition rather than a science, but the calendar is here if you follow it.
Pair the phase with the sunrise and sunset times for your location to know when the sky is actually dark, and use the countdown to count down to the next full moon.
Moon Phase Uses
Astronomy
Plan stargazing sessions around new moon dates for darker skies.
Photography
Schedule full moon photography sessions.
Gardening
Some gardeners follow lunar phases for planting schedules.
Frequently Asked Questions
How accurate is the moon phase calculation?
The calculation uses astronomical algorithms and is accurate to within a few hours for dates within several decades of present.
What are the 8 moon phases?
New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, Waning Crescent.
When is the next full moon?
The calculator shows the date of the next full moon and other upcoming lunar events.