Convert Week (week) to Month (Synodic) (month (synodic)) instantly.
About these units
Week (week)
A week consists of seven days, a structure stemming from ancient Babylonian and Near Eastern traditions that associated each day with a celestial body (Sun, Moon, and five visible planets). The seven-day week spread through Judaism, Christianity, and Islam, becoming one of the world's most persistent cultural time cycles. Unlike the day, month, or year, the week has no astronomical basis—its endurance is purely cultural. Yet it organizes labor systems, religious observances, markets, and global business schedules. The survival of the week across millennia demonstrates the remarkable staying power of cultural tradition, transcending scientific revolutions, political changes, and the rise of international standardization.
Month (Synodic) (month (synodic))
A synodic month is the time the Moon takes to complete a full cycle of phases—from new moon to new moon—lasting about 29.53059 days. Unlike the simple geometric orbit of the Moon, the synodic period aligns with the Sun–Earth–Moon relationship, making it tied to how humans perceive the Moon's illumination cycle. This is the month that shaped nearly all ancient calendars, from Babylonian to Hebrew, Islamic, and Chinese systems. Religious festivals, agricultural cycles, and early navigation practices all relied on the regularity of the synodic month. Even today, while civil calendars use fixed months, astronomical calculations and lunar calendars still depend on synodic months to track tides, eclipse cycles, and the dynamics of Earth's only natural satellite. The synodic month illustrates how natural celestial rhythms guided early human civilization.