Day of the Week

🗓️ What Day Were You Born?

Enter your birth date to see the day of the week you were born, the planet behind its name, and which weekdays your future birthdays land on.

The seven-day planetary week

The names of the days come from the seven classical celestial bodies — the Sun, Moon, Mars, Mercury, Jupiter, Venus and Saturn (the planetary week). Japanese weekday names are these bodies directly, and the English names correspond to the same week through Germanic gods (e.g., Tuesday = the day of Mars).

※ The weekday is a calendar fact. The planetary association is the origin of the name, not a fortune. About our data