📆 เครื่องคิดเลขวันในสัปดาห์

เกี่ยวกับเครื่องคิดเลขนี้

A day of the week calculator tells you which day a given date lands on — Monday through Sunday — for any date, past or future, using the browser’s proleptic Gregorian calendar. Alongside the weekday it reports the day number within the year (1–365 or 366), the ISO-8601 week number, whether the year is a leap year, and how many days remain until the end of the year. It is handy for planning events, checking historical dates, or working out which weekday a birthday or anniversary falls on in a future year.

You simply enter a date (or leave it blank for today) and it maps that date to a definite weekday using the proleptic Gregorian calendar built into every browser — the modern calendar rules projected consistently backward and forward in time. The same lookup yields the day-of-year number, the ISO week the date belongs to, and whether that year carries a 29 February, so a single answer covers several common questions at once.

For example, 4 July 1776 was a Thursday, and 1 January 2000 was a Saturday; enter your own birthdate and you can see which weekday you were born on, then check which weekday it falls on this year. People use it to plan events onto a particular weekday, settle "what day was I born" questions, verify a historical date, or work out that a fixed-date holiday shifts to a new weekday each year.