Note: If you have a paper money note, a non-US coin or an error coin, browse to the Pricing Paper Money, etc. page for places to get help. I don't know anything about these things other than what's on that page.
The real answer to the question is that your coin is worth whatever you can get someone to pay you for it. Even in the absence of someone taking advantage of you, this number can vary significantly. For example, a dealer will pay you less than a collector who is really interested in adding your coin to their collection.
There are three things that make coins valuable.
1) Scarcity. The rarer a coin, the more it is worth.
For example: an 1877 Indian head cent can sell for several hundred
dollars while an 1865 might sell for $10 and a 1903 for $1.50. It has nothing
much to do with the age of the coin.
a) The presence or lack of a mint mark can substantially change
the value of a coin because it is scarce.
b) A particular variety can be scarce as well.
2) Condition. The nicer condition a coin is in, the more it is worth.
Sometimes small differences in grade make big differences in cost, sometimes
not.
A 1926 S Quarter retails for $3 in good condition, but $650 in uncirculated,
and many thousands of dollars in choice uncirculated condition.
A 1909 S-VDB cent will sell for $600+ uncirculated, but is still worth
$300+ in very worn condition.
3) Demand. Even relatively common coins can demand a significant premium
if lots of people collect them.
For example, although 264,000 1916 D dimes were made, they sell for
$1600 in VF condition. In 1798, only 27,550 dimes were made, but they sell
for around $1000. Why? not because the 1916D dime is rarer, but because
more people collect mercury dimes than dimes from 1798.
Steps to Determining a U.S. Coin's Approximate Value
Values of Specific Common Coins
Now for some specifics. Here are the approximate values of some of the more commonly asked about coins. These are retail values. What a dealer will offer you is less, sometimes on the *really* common stuff, they don't even want it, as they have enough in stock to last 'til kingdom come.
1 cent pieces.
Indian Head Cents: 1859-1909 Average Indian head cents sell for around
75 cents.
Wheat cents: 1909-1958 These coins generally retail for 2c.
Memorial cents: 1959- Unless uncirculated, lunch money
5 cent pieces.
Liberty Nickels 1883-1912 Average coins sell for a dollar.
Buffalo nickels 1913-1938 Average dated coins sell for around 75 cents.
Dateless buffalos go for around 15 cents.
Jefferson nickels 1938- all but a very few
dates go for close to face value in circulated conditions. lunch money.
10 cent pieces
Barber dimes 1892-1916 Average coins sell for 1.25
Mercury dimes 1916-1945 Average coins sell for the price of silver,
about 45-50 cents depending on the market.
Silver Roosevelt dimes 1946-1964 Virtually all circulated coins sell
for the melt price of silver.
Clad Roosevelt dimes 1964-present lunch money unless uncirculated.
25 cent pieces
Barber Quarters 1892-1916 $3 in average condition.
Standing Liberty Quarters 1916-1930 $3 in average condition. dateless
go for melt value, about $1.15
Silver Washington 1932-1964 Most are melt value coins $1.15 or so.
Clad Washington - lunch money unless unc.
50 cent pieces
Barber 1892-1915 $5 in average condition.
Walking Liberty 1916-1947 $3 in average condition
Franklin Half 1948-1963 $2.25 in average condition (varies with silver)
Silver Kennedy 1964 $2.25 in average condition (varies with silver)
40% Silver Kennedy 1965-1970 $0.70 "
Dollars
Morgan dollars 1878-1921 $7 in average condition
Peace dollars 1921-1935 $7 in average condition
Eisenhower dollars 1971-1978 $1.30
SBA dollars 1979-1981 1979's are all lunch money, the 80s and
81s are a slight premium
The Value of a Coin
Just because a coin doesn't have great monetary value on the open market
doesn't mean it isn't interesting or that it doesn't have considerable
value to you. I invite you to browse our web page to learn more about your
coins. If you want to sell your coins, here are our basic offer
prices.