Moon phase app, widget and calendar

Install the Moon phase app

Open this page once while you are online, then add it to your device. From then on the app starts from its own icon and opens without a connection.

• Windows (Chrome or Edge): click the install icon at the right end of the address bar, or look for Install in the browser menu, and confirm.
• Mac (Chrome, Edge or Safari 17 and later): in Chrome or Edge, click the install icon in the address bar; in Safari, open the File menu and choose Add to Dock.
• Linux (Chrome, Chromium or Edge): click the install icon in the address bar, or pick Install from the browser menu.
• Android (Chrome): open the three-dot menu and tap Install app. Some versions word it Add to Home screen.
• iPhone and iPad (Safari): tap the Share button, scroll down to Add to Home Screen and tap Add.

Phase calculator

The phase, how much of the Moon is lit and whether it is waxing or waning, for any date from 1900 to 2100. Enter the time in UTC.

Observation journal

Write a note and it is saved with the Moon’s phase at that moment. Notes stay on your device.

Moon phase widget for your website

Choose a size, colors, a time zone and the Moon’s orientation; south up is the view from the Southern Hemisphere. The preview is the widget itself, and the code under it goes into your page’s HTML. The widget shows the current phase, how much of the Moon is lit, the Moon’s age in days and the date and time in your zone, and it refreshes itself every 5 minutes.

Preview

Embed code

The widget is made for web pages. On a phone, put the installed app on your home screen instead.

Add the Moon phases to your calendar

Pick a year, the phases you want and your time zone. Every phase becomes an event at its exact moment, titled with the phase name. Your calendar app shows each event in its own zone; the zone you pick here only decides which phases fall inside the year. For a month laid out as a grid, open the Moon calendar.

• Google Calendar: on a computer, click the plus next to Other calendars, choose From URL, paste the address and click Add calendar. The new calendar also appears in the phone app. To load the downloaded file once instead, use Settings, then Import & export.
• Apple Calendar: on a Mac, choose File, then New Calendar Subscription, paste the address and click Subscribe. On an iPhone or iPad, open the downloaded file from Files and tap Add All.
• Outlook: choose Add calendar, then Subscribe from web, paste the address and select Import. For the downloaded file, choose Upload from file in the same menu.