Coin Jar Calculator - Estimate Total Value

Coin jars accumulate surprisingly fast. Many people are shocked to find $50, $100, or even $200+ worth of coins in a jar they assumed held almost nothing. This calculator helps you estimate the value of a coin jar without counting every single coin.

US Coin Reference Values

The United States uses six commonly circulated coin denominations:

Weight-Based Estimation

If you know the approximate weight of your coin jar (without the jar), you can estimate value based on average coin composition. A “typical” mix of pocket change in the US contains roughly:

• 35% pennies (by count)
• 10% nickels
• 25% dimes
• 28% quarters
• 2% other

Work that mix out per 100 coins and you get 353 grams carrying $10.35, which is $0.029 of value per gram, or about $13 per pound of mixed US change. Depending on how your jar skews the answer lands somewhere between $9 and $17 per pound.

Here is the part that makes weighing coins work at all. A dime is 2.268 g and a quarter is 5.67 g, and both come to exactly $0.0441 per gram. So does a half dollar at 11.34 g. The Mint kept face value proportional to weight for that whole family, a habit left over from the silver era, and it never changed after the coins went to clad. Pennies ($0.004/g) and nickels ($0.010/g) are the outliers, and they are the reason a jar’s average sits so far below $0.0441: they are heavy, they are worthless, and they are what everyone throws in the jar instead of spending.

So the single best predictor of what your jar is worth is not how heavy it is. It is what fraction of it is pennies.

UK Coin Reference

For UK coins: 1p (3.56g), 2p (7.12g), 5p (3.25g), 10p (6.5g), 20p (5g), 50p (8g), £1 (8.75g), £2 (12g). A typical UK coin mix averages approximately £0.025–£0.030 per gram.

Jar Volume Method

A standard mason jar (1 quart / 946 ml) holds about 1,350 pennies, which is $13.50, or about 725 quarters, which is $180. A 1-gallon jar holds four times either: $54 of pennies, around $725 of quarters. A jar of ordinary mixed change lands in between, near $115 a quart, and anywhere from $80 to $150 depending on how many pennies are in it.

Those figures assume coins poured in loosely, which leaves roughly 40% of the jar as air between them. The same penny problem shows up again: a full jar of pennies is worth less than a tenth of a full jar of quarters.

This calculator accepts both coin counts and weight-based estimates.

The Coinstar fee

Coinstar kiosks take a cut when you ask for cash, and the kiosk shows it on screen before you start. Recent reports put it around 11.9% to 12.9% plus a transaction fee of up to $0.99, and Coinstar says up to 15.9% at some locations (as of September 2026). The fee varies by kiosk, so enter the one yours shows. Take the gift card or eGift card option instead and there is no fee at all.