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Date & Time
Moon Phase Calculator
Check today or another date using a lightweight astronomical approximation that runs locally in your browser.
—Phase
—Lunar age
—Illuminated
—Cycle progress
🌙Approximate lunar phase
Uses a synodic-month approximation referenced to a known new moon. It is useful for everyday phase checks but is not an ephemeris for precision astronomical work.
Core timing workflows
Start with a direct timer, stopwatch, alarm or focus workflow. Calendar, date arithmetic, clocks and scheduling specialists remain available from the full Date & Time hub.
Online TimerCountdown, sound, repeat & fullscreenStopwatchLaps, precision & fullscreenCountdown TimerFocused countdown workflowAlarm ClockAlarm at a local clock timePomodoroFocus and break cyclesInterval TimerWork/rest roundsPresentation TimerTalk timing with warningsClassroom TimerProjector-friendly countdown