Your spare change can add up to real cash and you can take this cash to the bank. Keep track of your change by sorting it according to denomination and keeping each denomination in a separate container. You can estimate the value of each container of coins by first weighing the filled container. Then, you divide the weight of the coins in the container by the weight of one or a small number of coins of that denomination. Weighing coins is also helpful when selling large batches of inexpensive collection coins such as wheat cents.
Things You'll Need
 Kitchen scale (preferably digital)
 Handheld calculator
Weighing the Coins

Empty the bag or container of all coins. Weigh the bag on the scale. Note the weight of the bag.

Refill the bag or container with all coins to be weighed. Place on the scale and note the result.

Subtract the weight of the bag or container from step 1 from the weight of the full bag or container in step 2.

Note the result. Remove the bag of coins from the scale. If you are weighing coins for reasons not connected to their nominal value, this is the final step. If you want to know the full value of the coins you have in your container or bag, follow the steps in Section 2 to compute that value.
Computing the Value of the Coins

Convert the weight of the full amount of the coins to metric weight (grams) by multiplying the result in Section 1, Step 4 by 2205. For example, if you have 10 pounds of coins, you would multiply 10 by 2205 to get 22050.

Divide the metric weight of the coins by the official US Mint weight of the denomination of the coin as follows: Penny: 2.5 g; Nickel: 5.0 g; Dime: 2.268 g; Quarter: 5.670 g; Half Dollar:11.340 g. If the coins in the example above are nickels, you would divide 22050 by 5.0 (5) to get 4410.

Multiply the decimal value of the coin by the result in step 2. The decimal value of each denomination of coin is as follows: a penny is 0.01, a nickel 0.05, a dime 0.10, a quarter 0.25 and a halfdollar 0.50. The result is the full value of the coins. The full value of ten pounds of nickels is $220.50, as that is the result of 4410 multiplied by 0.05.
Tips & Warnings
 Note that round weights are rare, except when dealing with pennies or nickels. You may get a slightly inaccurate result, as the scale you use to weigh your coins will not be as exact as the official US Mint calibrations.
References
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