See today's moon phase, a full monthly calendar of moon phases, the next full and new moon with a countdown, the current moon sign, and the best days this month for planting, fishing, haircuts, and manifestation.
As the Moon orbits Earth roughly every 29.5 days, the portion of it lit by the Sun and visible from Earth changes in a predictable, repeating cycle traditionally divided into eight named phases. New Moon marks the start of the cycle, when the Moon sits between Earth and the Sun and its near side is unlit — invisible from Earth. Over the following two weeks, the illuminated portion grows (waxes) through Waxing Crescent, First Quarter (half-lit), and Waxing Gibbous, culminating in the Full Moon, when the Moon sits opposite the Sun and its entire near side is lit. From there, the illuminated portion shrinks (wanes) through Waning Gibbous, Last Quarter (half-lit again, the mirror of First Quarter), and Waning Crescent, before returning to New Moon and starting the cycle again. This tool calculates exactly where in that eight-phase cycle any given date falls, using the Moon's well-documented average orbital period.
The core calculation converts a calendar date into a Julian Date — a single continuous number astronomers use instead of a year/month/day breakdown, which makes date arithmetic simple. It then measures the difference between that Julian Date and a known reference point (a New Moon that occurred on January 6, 2000), and takes that difference modulo the Moon's average synodic period of 29.53058867 days — the precise, well-documented average time between one New Moon and the next. The result is the Moon's 'age': how many days have passed since the most recent New Moon, somewhere between 0 and about 29.5. That age is then compared against the traditional day-ranges for each of the eight phases (New Moon at 0–1 days, Waxing Crescent at 1–7, and so on) to determine which phase is currently showing.
While the Sun takes a full year to travel through all twelve zodiac signs (which is why your sun sign only depends on your birth month and day), the Moon completes the same journey roughly every 27.3 days — meaning it changes zodiac sign every two to three days. This tool estimates the Moon's zodiacal position using its mean orbital longitude, a standard simplified astronomical formula that tracks the Moon's average motion without modeling every small gravitational perturbation from the Sun and planets. The result is accurate enough to correctly identify the Moon's sign for the great majority of dates, with a small chance of being off by one sign right at a boundary transition — a limitation shared by any moon-sign calculator that doesn't run a full ephemeris.
Long before satellite forecasts and modern agriculture, farmers, gardeners, and fishers across many cultures tracked the Moon's phase to time their work, and many of those traditions persist today in almanacs and folk calendars. The general logic behind lunar gardening holds that the Moon's waxing light (growing from New to Full) favors growth-oriented activities — planting above-ground crops and, by extension, cutting hair for faster regrowth — while the waning half favors activities associated with rest, pruning, or root development. Separately, 'solunar theory,' popularized in the early 20th century, links increased wildlife (especially fish) activity to the New Moon and Full Moon, when the combined gravitational pull of the Moon and Sun on Earth's tides is at its strongest. This tool applies both traditions consistently, day by day, based on each date's calculated phase.
In more contemporary spiritual and self-development practice, the New Moon and Full Moon are often treated as the two anchor points of a monthly ritual cycle: the New Moon, with the Moon's light at its lowest, is associated with setting new intentions and starting fresh — a symbolic blank slate. The Full Moon, at peak illumination roughly two weeks later, is associated with culmination, high energy, and release — a natural point to reflect on progress or let go of what isn't serving you. This tool flags both of these dates each month as favorable for manifestation work, alongside the calculated moon phase for every other day, so you can plan intention-setting or reflection practices around the actual lunar calendar rather than an arbitrary date.
Whether or not you find personal meaning in lunar timing traditions, this tool is built to be a genuinely useful reference calendar: an at-a-glance view of exactly which moon phase falls on which date, for any month you want to check, computed with real astronomical arithmetic rather than a lookup table that needs updating. Gardeners, photographers planning around moonlight, stargazers timing a dark-sky session around the New Moon, or anyone simply curious what the sky looked like on a specific date can all use the same monthly view and next-event countdowns. The traditional 'best days' guidance is there as an optional layer on top — useful if that framework resonates with you, and easy to ignore if you're just here for the astronomy.
Moon Phase Calendar is one astrology tool among several. These related tools cover other birth-date-driven insights.