Guesstimates Spare Change is a simple and straight forward site aiming to estimate how much moola you have stashed away in your change jar. All you need to do is weigh your jar of coins, grab a handful as a sample and enter the quantity of each coin you pulled out into the CoinCalc form. The site does a little math and guesses how much money is in the jar based on your sample.

Coin Cup

I just happened to have a jar full of coins that needed to be tallied and wrapped up so I though I would give a run for it’s money (pun intended). I took 5 samples of various sizes from the same cup of coins. After counting the number of coins I would put them all back in the cup and shake them around to keep it as fair of a test as possible. I happen to have a small postal scale at hand so calculating the weight of the coins was a snap. My first weighing included the weight of the cup which came to a total of 3.375 pounds. After running all of the numbers through, I realized the weight of the cup was inflating the estimate. I weighed the empty cup and subtracted that weight from the previous weight resulting in 2.8625 pounds of pure coinage. The results are summarized in the table below:

Sample Pennies Nickels Dimes Quarters Estimated Total Estimated Total
w/o Cup
1 36 0 10 20 $43.07 $36.53
2 23 4 3 9 $33.71 $28.59
3 16 3 5 7 $36.96 $31.35
4 31 3 14 11 $37.82 $32.07
5 13 2 6 11 $46.26 $39.23

The total value of my coin-collection was $28.91 which came out to the following:

Coin Quantity Value
Pennies 211 $2.11
Nickels 33 $1.65
Dimes 59 $5.90
Quarters 77 $19.25
Total 380 $28.91 came within $10 at most of the actual value after correcting for the weight of the cup. CoinCalc’s estimation was more accurate than I thought it would be. The site gives you a good ballpark range of the value of your coins without having to dump them all over the floor and count them out one by one or paying a fee to have Coinstar count them for you.

Speaking of counting, I like to wrap my own coins and I use this little device from MMF Industries pictured below to tally them up before wrapping.

Plastic Coin Counter

You simply dump your sorted coins into their respective slot and the plastic container will keep them stacked until they reach the top. At that point there is a slit where surplus coins fall out leaving you with the exact quantity for the roll. I think I got this from my parents a couple of Christmas’ ago.

(via BoingBoing)

5 Responses to “ Guesstimates Spare Change ”

  1. Hello Russell,

    I want to thank you for doing an in depth test of it and posting the results of each test as it is interesting to see how it works for people. This page has been added as a link from the main coincalc page so other people can also see the results of your tests.

    Best Regards,


  2. you know what I just don’t get? what’s so bad about slowly counting change? I find it to be enjoyable and relaxing!


  3. Wow, that’s a very detailed report you have there. Having a machine to count your coins is what I called the smart way of doing things :)


  4. Man oh Man, whut will they think of next, a machiney thingamabob that can count yer pocket change, that is ifna ya’ll don’t have a hole your coverall pockets. Whooee boy. I got sumtin to tell the fellers at the corner store now.


  5. […] are mixed opinions on this. For the inside scoop on this particular coin calculator, check out Russell Heimlich’s fun experiment with coins he had lying around as spare […]

Leave a Comment of Your Own

Warning: mysql_query() expects parameter 2 to be resource, object given in /home/russellheimlich/ on line 98