Lunar Cycle Length Calculator
Work out the precise length of one lunar cycle and how it shifts over time.
Mean lunar cycle length
29.53 days
One full lunar cycle (new moon to new moon) lasts 29 days, 12 hours, 44 minutes. This is called the synodic month.
About the Lunar Cycle Length Calculator
The lunar cycle length calculator is a free online lunar calculator that gives you an accurate answer in seconds. Work out the precise length of one lunar cycle and how it shifts over time. Just pick a date and the calculator does the rest, using the same astronomy math NASA uses to track the moon.
People also search for this as a lunar cycle length, synodic month, moon cycle days. Whatever you call it, this moon calculator is built to be fast, accurate, and easy to use on any phone or computer. There is no sign up, no download, and no cost — just open the page, type your date, and read the answer.
Every number on this page comes from a real moon phase calculation engine. That means the moon phase, the moon age, the illumination percent, and the moon distance are all computed from the same formulas used in astronomy textbooks. You can trust the result for school projects, sky watching plans, or simple curiosity about the night sky.
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