Next Full Moon Calculator - Free, Instant, In Your Browser
Enter a date to find how many days until the next full moon.
How to use Next Full Moon Calculator
- 1Enter the required date(s) and details above.
- 2Click Calculate - Next Full Moon Calculator runs instantly, right in your browser.
- 3Read your result below.
Your file is processed in your browser and is never uploaded.
Frequently Asked Questions
What's the formula?
Calculated using the synodic (lunar) month of 29.53 days from a known reference full/new moon.
Is my data sent to a server?
No - everything runs entirely in your browser with JavaScript. Nothing is uploaded.