This distraction comprises everything you could possibly want to know about our U.S. coins except the composition ... too depressing. A quarter is actually a useful measuring device unless you already have a ruler in your pocket protector.   The diameter is just under an inch and the thickness is about 70 mils. If you're really desperate for a measurement, you can roll the quarter along the surface.  Each complete rotation covers three inches. Dimensions below are metric. coin front back diameter thickness weight penny A. Lincoln Lincoln Mem. 19.1 mm 1.55 mm 2.5 g nickel T. Jefferson Monticello 21.2 mm 1.95 mm 5.0 g dime F. Roosevelt torch, olive, oak 17.9 mm 1.35 mm 2.27 g quarter G. Washington eagle or state 24.3 mm 1.75 mm 5.67 g