The Moon's orbital period, or the time it takes to complete one full orbit around the Earth, is approximately 27.3 days. This is often rounded up to 28 days for convenience.

However, it's important to note that the Moon's synodic period, which is the time it takes for the Moon to return to the same position relative to the Sun (as seen from Earth), is actually slightly longer than 28 days (about 29.5 days). This is the reason why the lunar cycle, which is the basis for our calendar months, is approximately 29.5 days long.