How much does a quarter weigh?

A US quarter has a mass set by law, not left to chance: the Mint's specification for the copper-nickel clad coin struck since 1965 is exactly 5.670 grams. That is one of the few numbers on this site that is not an estimate — a coin fresh from a bank roll weighs almost precisely that, and even a well-worn one is only a few hundredths of a gram lighter.

Because every quarter is struck to the same size and weight, it doubles as a built-in ruler: photographed next to something unknown, its fixed diameter — 24.26 millimeters — gives a scale for judging size, which is often the first step toward guessing weight for anything that is not itself a coin. Quarters minted before 1965 were 90 percent silver and weighed slightly more, at 6.25 grams, but every quarter made since has used the same copper-nickel clad specification, so the figure on this page covers everything still likely to turn up in change.