Moon phase
The moon phase for any date, with illumination and upcoming full moons.
- Instant
- Free
- Private (processed locally)
- No sign-up
Where is the Moon tonight?
Whether you’re planning a night photo, a stargazing trip or gardening “by the moon”, this tool gives the exact phase for a date: its name, emoji, illumination percentage and age in days. It also shows the next new and full moons.
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Choose the date
Today by default, or any past or future day.
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Read the phase
Name, illumination and moon age at a glance.
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Plan ahead
The dates of the next new and full moons are shown.
The 8 phases of the lunar cycle
| Phase | Illumination | Age (days) |
|---|---|---|
| 🌑 New moon | 0% | 0 |
| 🌓 First quarter | 50% | ≈ 7.4 |
| 🌕 Full moon | 100% | ≈ 14.8 |
| 🌗 Last quarter | 50% | ≈ 22.1 |
Calculation based on the average synodic month (29.53 days) from a reference new moon: accurate to about half a day, ideal for everyday use but not for eclipse calculation.
Frequently asked questions
What is the illumination percentage?
It is the share of the visible lunar disc lit by the Sun: 0% at new moon (dark side facing us), 100% at full moon, 50% at the quarters. It does not say whether the moon is waxing or waning — the phase name tells you that.
Why does the cycle last 29.5 days, not 27?
The Moon orbits Earth in 27.3 days (sidereal month), but during that time Earth moves around the Sun. It therefore takes about 2 extra days — 29.53 days (synodic month) — to return to the same phase. That is the cycle this tool uses.
Is the result accurate to the minute?
No: this synodic calculation gives the phase to within about half a day, enough for the phase name and illumination. Precise astronomical ephemerides account for the elliptical orbit and perturbations, which this tool simplifies.
What is a gibbous moon?
It is the phase between a quarter and full moon, where more than half but not all of the disc is lit. “Waxing” before the full moon, “waning” after. The term comes from the Latin gibbus, “hump”.