In one sentence, describe what the following article is about:

Many large stores have coin-counting machines, which rapidly count inserted mixed coins and returns paper money. However, these usually charge you a percentage of your total coin value as a fee, or gives you full value only in the form of a gift certificate to certain retailers. Certain banks have similar services, but usually only for customers. In Canada or the eastern U.S., even non-customers can use the coin-counting machines at BMO (Bank of Montreal) or TD Bank, although there may be fees. Find the nearest location of a BMO coin-counting service here. Coin-sorting machines for home use separate coins of different types into their own stack, or even into prepared paper wrappers. These range from a stack of cheap plastic trays with different sized holes, to machines that cost several hundred dollars or euros, and sort the machine in fast or visually appealing ways. Cheap, electronic coin-counting machines may jam after a few uses. Look for reviews online before buying one. Because coins are minted with a precise size and composition of metals, each one weighs a certain, predictable amount. You can estimate the value of a mixed coin collection using CoinCalc.com or for U.S. coinage, or separate them by type and weight them for a more accurate result:  One pound of quarters is worth $20. One pound of dimes is worth $20. One pound of nickels is worth about $4.50, and one pound of pennies is worth about $1.80.  One kilogram of two-euro coins is worth about €235. One kilo of one-euro coins is worth about €133. One kilo of 50-cent euro coins is worth about €64. A kilo of 20-cent coins is worth about €35, a kilo of 10-cent coins is worth about €24, a kilo of 5-cent coins is worth about €13, a kilo of two-cent coins is worth about €6.67, and a kilo of one-cent coins is worth about €4.35.  In the United Kingdom, banks will weigh bags of coins for you.

Summary:
Use a coin-counting machine at a supermarket or your bank. Buy a coin-sorting machine. Measure your change collection's value by weight.