Moon Phase Calculator


Moon phases from to   (enter four-digit years) — calculate

Use locale settings:     (support varies)
(doesn’t work for all locales)

Phases:  0.00 new, 0.25 first quarter, 0.50 full, 0.75 third quarter.

Times are given in Coordinated Universal Time, and local time using your system’s time zone and daylight saving time settings.

Calculations are based on the “higher accuracy” equations in Astronomical Algorithms, second edition, by Jean Meeus, and the full VSOP87 data set.

Updated 5/8/2021 to fix a bug displaying the month in local time.







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