Moon Phase Zodiac Sign Calculator
This moon sign calculator finds which zodiac sign the moon is in on any date you pick. It's a different calculation from the moon's illumination phase (new, full, crescent) covered by the rest of this site -- the zodiac sign tracks the moon's position against the background stars, not how much of it is lit.
How to use this tool
Pick a date and your time zone. Adding a time is optional but helps -- the moon changes sign roughly every 2 to 3 days, so on some dates it changes sign partway through. If you leave the time blank and that happens to be one of those dates, we'll show you both signs it could have been instead of guessing.
Moon sign vs. moon phase
These are two completely different things that happen to share the word "moon." The phase (new, full, crescent, and so on) is about how much of the moon is lit, and it's the same everywhere on Earth at any given moment. The zodiac sign is about which of the 12 constellations of the zodiac the moon appears in front of, astronomically, and it changes roughly every 2 to 3 days as the moon orbits Earth -- unrelated to its phase.
The moon's position is calculated using a documented medium-precision formula (a 12-term perturbation series, the same public reference tier as Meeus's Astronomical Algorithms) rather than the simpler mean-cycle formula used for this site's phase calculators, since a zodiac sign boundary is a hard edge that needs more precision than a percentage does. We checked this implementation against five real, independently published moon sign-change times for September 2026, and it landed within about 1 to 4 minutes of each one.
Common questions
How is this different from my "star sign"?
Your star sign (or "sun sign") is the zodiac sign the sun was in when you were born, and it stays fixed for you. The moon's zodiac sign changes every 2 to 3 days, so this tool tells you where the moon is right now or on a date you pick, not a fixed personal placement.
How accurate is this?
We checked it against five real, independently published moon sign-change timestamps for September 2026, and it landed within about 1 to 4 minutes of each one. Near the exact moment of a sign change, results within a few minutes of that boundary carry a small margin of error.
What if my birth date has two possible moon signs?
The moon changes sign roughly every 2 to 3 days, so on some dates it moved from one sign to the next partway through the day. If you know your birth time, enter it above and we'll give you one answer. If you don't, we'll show you both signs it could have been so you're not getting a guess dressed up as a fact.
Does this affect the moon phase shown elsewhere on this site?
No. Zodiac sign and illumination phase are calculated completely separately and don't affect each other.