Last Quarter at birth
Last Quarter illustration
Last quarter (also third quarter) again shows about half the Moon lit, now on the opposite side from first quarter.
Morning sky watchers often catch last-quarter moons high before dawn.
Place in the cycle
The Moon takes a bit over twenty-nine and a half days to return to the same phase. The Last Quarter is the seventh of the eight labels this site uses between one new moon and the next.
How this site estimates your phase
The birthday calculator has your date, not your birth minute. We evaluate a simple average lunar cycle at local noon and map that progress into eight named windows. That is good enough for curiosity and teaching; orbital ephemerides used by observatories are tighter when you need precision.
Read more in methodology or return to the moon phases hub.
Common questions
What does a Last Quarter look like?
From Earth you see illumination that is about 50% and waning. Exact appearance still depends on your latitude, the Moon's path, and weather.
How does the calculator decide I had a Last Quarter?
It estimates phase at local noon on your birth date with a mean synodic-month model, then bins the result into one of eight classic names.
Can the label be wrong without a birth time?
Yes, near phase boundaries. Without clock time and location, neighboring names can be equally plausible.