Lunar Calendar – Monthly Moon Phases

View a monthly lunar calendar showing moon phases for every day.

How It Works

Select a month and year. The calendar computes the moon phase fraction for each day and displays the corresponding phase emoji and name.

Formula

Phase per day = ((julianDay - 2451550.1) / 29.53059) % 1

Frequently Asked Questions

How many moon phases are in a month?

Each calendar month typically contains all 8 moon phases: New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter, and Waning Crescent.

Does every month have a full moon?

Almost always. Most calendar months have exactly one full moon. Occasionally February can miss a full moon if the full moon falls in late January and early March.