How to Measure Your Coins

Measuring the dimensions of your coins is extremely important, if you don’t know this information then how will you be able to protect them? Not only do you need to know the diameter of your coin, but you should also measure the depth. We have provided three ways to best measure your coins. Of course you can always do a Google search for your coin, but what do you do if there are no results? We will walk you through how to measure our 1oz American Silver Eagle coin with each step. According to the manufacturer, this coin has a diameter of 40.6mm and a depth of 2.98mm, let's see how close we can get with each step.

Measuring your coin with a Caliper. This will be the most accurate way to measure your coins. Make sure your caliper is set to mm, and adjust it to the widest part of the coin for the diameter, then measure the depth. See our example photo, as you can see on the caliper it measures 40.6mm and it has a depth of 2.98mm. Now that we have these measurements we can skip to Step 4.


Measuring with a Ruler in Inches. 

This is the may be the most common way to measure coins for those in the USA, but it includes the most amount of work. You will need to get the best measurement you can for the diameter and the depth. Make sure to have your ruler at the widest part of the coin. Then do a Google search to convert inches to millimeters. If your coin comes up to a fraction, you will need to divide your numerator by your denominator to get a decimal. 

Google Measurement Converter

Our coin has a diameter of about 1-9/16” and a depth of about 3/32“. In the converter we will enter 1.6 as our diameter and 0.09375 as our depth, and this tells us our coin measures 40.64mm by 2.38mm. As you can see the measurements for our coin is slightly off, but we will get a close estimate.

Measuring with a Ruler in Centimeters. This option will be much easier calculations than measuring in inches. Just turn your ruler around to cm, and measure your coin. Once you have this measurement multiply it by 10, you now have the dimensions in mm. Our coin measures a little over 4cm and we multiply this by 10 and our diameter is about 40mm.



Step 4: Now that you have your measurements, you can shop for coin capsules. Shop under the “Air-Tite Coin Capsules & Holders” category. This will open a list of every size capsule we carry, and they are sorted by coin diameters. As our example coin measures 40.6mm diameter, we will shop in the 40mm category. This will show us all the options for this diameter coin. 

Once we find a listing we are interested in, we click into it and make sure the inside depth of the capsule will fit our coins. Verifying that they will, we can now place our order.


Important Note: We always recommend measuring your coins, even common coins may be slightly off from the manufacturer’s measurements. If you need any help figuring out the dimensions of your coin, please let us know and we will be more than happy to help.

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