1" is equivalent to 1 quarter diameter.
2" is equivalent to the height of a credit card, the length of an average sized thumb, or 2 quarters side by side.
3" is equivalent to half the length of a dollar bill, the length of a credit card, the diameter of a coffee mug, or 3 quarters side by side.
4" is equivalent to the width of most coasters, width of an average size palm (to crevice of thumb), the length of a computer mouse or 4 quarters side by side.
5" is equivalent to the height of a soda can, the length of a highlighter, length from the average wrist to the top of your baby finger, or 5 quarters side by side.
6" is equivalent to the length of a dollar bill, a Bic pen with the cap on, or 6 quarters side by side.
7" is equivalent to the length of the average sized hand from the wrist to the top of the middle finger, or 7 quarters side by side.
8" is equivalent to a little less that the width of a piece of copy paper, or 8 quarters side by side.