18 inches by 22 inches

A fat quarter is a 1/2 of a metre and then cut in half so is half a metre by half the width

Depends where you are from as not every country uses metric if its a Yard or Metric it still gets cut into Quarters Hence the name a fat Quarter

so is the variation in fat quarter sizes because of the width of the fabric??

I see that it varies according to where one lives or buys fabric.
Thanks for the questions.
*4u!
Jacqueline

Any True Quilting site will tell you that a REAL FQ size is 18" x 22" no matter what part of the world you are from and has nothing to do with cutting fabric in half and then in quarter etc!

Convert the above size to metric if need be but this IS the Standard Size for a FQ and accepted /used Worldwide!

This Size based upon for use in Quilting Books etc!

*4U!

The size of a fat qurter is 18" X 22". That is what is used in quilting. Have fun.

HERE A FAT QUATER IS ONLY 5X5 CAROLYN

I see you got your answer, I always like to buy fat quarters they are nice to have on hand, but they are getting expensive, sometimes it is better to buy the whole yard.****

A Fat Quarter==18X22....But in that fat quater
There are:
99-2" squares
50-2 1/2" Squares
42-3" Squares
30-3 1/2 Squares
20-4" squares
16-4 1/2" Squares
12-5" squares
9 -5 1/2" squares
9 -6" Squares
6 -6 1/2" Squares
WOW, did you ever realize what a bargain a Fat Quarter was???