Template:CURRENTISOYEAR/doc

This templates returns the ISO year number for today (as set by UTC time on the Wikipedia server).

The ISO year (always equal to the gregorian year between January the 4th, in ISO week 1, and December the 28th) always includes an integer number, 52 or 53, of ISO weeks starting each on Monday and ending on Sunday; the ISO year may be smaller (by 1) on the first zero to three days of January, and may be larger (by 1) on the last zero to three days of December.

Usage
gives