The moon on the day you were born, from any date between 1900 and 2100.
Birthday moon phase
What moon were you born under?
Enter a birth date to see the moon's phase that day, how much of it was lit, the sign it stood in and the lunation type astrology reads from it. Add a birth time for the exact moon sign.
The calculator needs JavaScript. The eight phases and what each is read for are listed just below.
How to find the moon phase on your birthday
- Enter your birth date. The time is optional; without it the calculator uses noon.
- Read your phase, how much of the moon was lit, and the sign the Moon stood in.
- If you were born on a new, quarter or full moon day, it shows the exact time, and for a full moon its folk name or a Blue Moon.
- Copy the link to share your result, or open that month on the moon phase calendar.
The phase is the same everywhere on Earth at the same moment, so a birthday moon travels with you. Only the date can shift: near midnight, someone born in Tokyo and someone born in New York at the same instant have different calendar dates.
The eight birth moon phases
| Phase at birth | Lunation type | How astrology reads it |
|---|---|---|
| New moon to crescent | New Moon | Instinct and fresh starts, acting first |
| Waxing crescent | Crescent Moon | Pushing forward, breaking from the past |
| First quarter | First Quarter Moon | Action under pressure, the builder |
| Waxing gibbous | Gibbous Moon | Refinement, analysis, perfecting |
| Full moon | Full Moon | Illumination, relationship, seeing clearly |
| Waning gibbous | Disseminating Moon | Sharing, teaching what was learned |
| Last quarter | Last Quarter Moon | Reorientation, turning toward what comes next |
| Waning crescent | Balsamic Moon | Release, vision, closing a cycle |
The lunation types come from the astrologer Dane Rudhyar's The Lunation Cycle (1967), which splits the month into eight 45-degree steps of the angle between Sun and Moon. The visual phase and the lunation type usually match; on the days around a quarter they can differ by one step, so the calculator shows both.
Moon sign and birth time
The Moon moves through a zodiac sign in about two and a half days, so on roughly one birthday in three it changes sign that day. The calculator flags it, and a birth time settles which sign it was. For practice by phase, the guide to moon magic covers what each phase is traditionally used for, and the tarot birth card calculator turns the same date into your Major Arcana birth cards.