Week Number Today

The week number on this page follows ISO 8601, the international standard used across Europe, in global business planning and in most software. Its weeks start on Monday, and week 1 is the week that contains the year's first Thursday — the same as saying the week that contains 4 January. That is different from the week most people actually see day to day here: the wall calendar, the school planner and most PH-market apps start the week on Sunday, so the ISO week number on this page will not always match what a Sunday-start calendar shows for the same date.

That ISO rule has two other consequences worth knowing. A year has 52 weeks in most years and 53 in some, and the first few days of January can belong to the last week of the previous year, while the last few days of December can belong to week 1 of the next. The week table on this page shows the Monday and Sunday of every ISO week, so the boundaries are never a guess.

Because the everyday calendar in the Philippines starts the week on Sunday — the same convention the US uses — this page also shows that Sunday-start count next to the ISO one. Its week 1 is whichever week contains 1 January, however few days of the new year it holds, so it does not follow ISO's "first Thursday" rule.

In some years the two numbers match for most of the week and only split on Sundays; in others the Sunday-start number runs one higher for weeks at a time. Neither is wrong — they are two different rules for the same calendar — but a week number is only useful when both sides mean the same one. If a school, an office or a supplier quotes a week number, check which rule they mean before comparing it to your own.

The day of the year counts from 1 on 1 January up to 365, or 366 in a leap year. The Julian date on this page is the form used on food packaging, in manufacturing and in military logistics — the last two digits of the year followed by the day of the year in three digits, so 23 September 2026, day 266, is written 26266.

Astronomers use a different Julian date: a running count of days from a fixed point in 4713 BC. This page shows that one too, labelled Julian Day Number, so it is worth checking which "Julian date" a document actually means before treating the two as interchangeable. The days-left figure is simply how many days remain in the year after today — the number most people actually want when they are counting down to the end of the year.