Free lunar tool · 1900–2100
Moon Phase Calculator: What Moon Were You Born Under?
The Dreaming Zodiac Moon Phase Calculator shows the moon on any date from 1900 to 2100: its phase, how much of it was lit, its age in days, its zodiac sign and its distance from Earth. Enter your birthday to see the moon you were born under, and whether the nearest full moon was a supermoon.
Find the moon for any date
How it works
How the moon phase is calculated
A moon phase is simply the angle between the Moon and the Sun as seen from Earth. At 0° the Moon sits between us and the Sun and its lit side faces away – a new moon. At 180° it is opposite the Sun and fully lit – a full moon. One full cycle, the synodic month, lasts on average 29.53 days, which is why a calendar month sometimes holds two full moons.
The calculator works out that angle for your chosen day, the share of the disc that is lit, and how many days have passed since the last new moon (the Moon's age). It also finds the surrounding new and full moons to the minute, shown in your own time zone.
The eight phases
Moon age, light and birth type by phase
| Phase | Age (days) | Lit | Birth type |
|---|---|---|---|
| New Moon | 0–1 | 0–2% | The Initiator |
| Waxing Crescent | 1–7 | 2–49% | The Striver |
| First Quarter | about 7.4 | 50% | The Builder |
| Waxing Gibbous | 8–14 | 51–98% | The Refiner |
| Full Moon | about 14.8 | 98–100% | The Illuminator |
| Waning Gibbous | 15–22 | 98–51% | The Messenger |
| Last Quarter | about 22.1 | 50% | The Reformer |
| Waning Crescent | 23–29.5 | 49–2% | The Seer |
The astrologer Dane Rudhyar described eight “lunation types” in 1967: people born in the waxing half tend to build and start, those born in the waning half tend to share, question and complete. It is a symbolic lens for self-reflection, not a scientific personality test.
Distance
Supermoon or micromoon?
The Moon's orbit is an ellipse, so its distance swings between roughly 356,400 and 406,700 km. A full moon near the close point (perigee) is popularly called a supermoon – a term coined by astrologer Richard Nolle in 1979 – and looks up to about 14% larger and 30% brighter than a micromoon at the far point (apogee).
Dreaming Zodiac labels a full moon a supermoon below 360,000 km and a micromoon beyond 405,000 km. Definitions vary slightly between sources, so a borderline full moon may be called a supermoon on one site and not on another.
Frequently Asked Questions
What moon phase was I born under?
Enter your date of birth in the calculator above. It finds the Moon–Sun angle for that day in your time zone and names one of eight phases – from New Moon to Waning Crescent – together with the percentage of the disc that was lit and the Moon's age in days.
Is my birth moon phase the same as my moon sign?
No. The phase describes how much of the Moon was lit (its angle to the Sun); the moon sign is the zodiac sign the Moon was passing through. The Moon changes sign every two to three days, so a full birth chart needs your birth time – the calculator shows the sign for the middle of the day.
How accurate is the moon phase calculator?
New and full moon times are calculated with Jean Meeus' lunar theory and agree with the US Naval Observatory to within a few minutes for dates we tested between 1992 and 2026. Distance is accurate to a few hundred kilometres – enough to tell a supermoon from a micromoon.
Was there a supermoon on my birthday?
The calculator checks the full moon nearest your date. If the Moon was closer than 360,000 km at that full moon, it was a supermoon; farther than 405,000 km makes it a micromoon. Roughly three or four full moons a year qualify as supermoons.
Why can the moon phase differ by one day in another country?
The exact moment of a full or new moon is the same everywhere, but the calendar date is not. A full moon at 01:00 UTC on the 24th is still the evening of the 23rd in New York, so the calculator uses your own time zone.
Method & Sources
Phase, illumination and moon sign come from the same calculation as the Dreaming Zodiac moon calendar (Meeus' lunar theory); new and full moon moments are found by bisection to the minute and were checked against the US Naval Observatory. Distance uses Meeus' main distance terms. Birth-phase types follow Dane Rudhyar's lunation cycle, rewritten in our own words.
- J. Meeus (1998). Astronomical Algorithms, 2nd ed., ch. 47–49 (position and distance of the Moon, phases). Richmond: Willmann-Bell.
- US Naval Observatory – Phases of the Moon (Astronomical Applications Department). aa.usno.navy.mil/data/MoonPhases
- NASA Science – Supermoons. science.nasa.gov/moon/supermoons/
- D. Rudhyar (1967). The Lunation Cycle: A Key to the Understanding of Personality. Santa Fe: Aurora Press (1986 ed.).
Written by the Dreaming Zodiac editorial team · Last updated