Lunar Phase Calculator

Determine the exact phase and illumination of the moon for any date in history or the future.

Select Observation Date

Select a valid date to calculate the lunar phase.

About Lunar Phase Calculator

This is a free, fast, and fully client-side lunar phase calculator tool. All processing is done locally within your browser to ensure maximum privacy and security. No data is sent to our servers. Bookmark this page for quick access to ad-free, high-performance SEO and developer utilities.