Rubber Band Sizes (and Size Chart)

Rubber bands are great for a million things, the most notable of which is making humungous rubber band balls. However, making a large ball or keeping things together requires finding the appropriate rubber band size. So, what sizes do rubber bands come in?

Rubber bands range from 7/8 to 7 inches long and 1/16 to 1/8 of an inch wide and measure about 1/32 of an inch thick.

If you take a look at different suppliers, you might find that they sell over a dozen rubber band sizes. So, in today’s guide, I’ll share with you a rubber band size chart and how to measure and grade a rubber band.

Rubber Band Size Chart

Below is a chart describing standard rubber band sizes. Please note that the walls of standard rubber bands are 1/32 of an inch thick.

The figures above describe the standard set of rubber band sizes. If you’re looking for customized sizes, you should reach out to the supplier to see what they can do.

How to Measure a Rubber Band

When looking at different rubber band sizes, there are 3 measurements you have to consider—flat length, width, and wall thickness.

To measure a rubber band, you should do the following:

• Pinch both ends of the rubber band and attempt to lay it flat on a table or another horizontal surface. Make sure that the rubber band is not twisted in any way.
• Use a ruler and carefully measure the distance from one end of the rubber band to the other. This will give you the flat length measurement.
• To measure the width, measure the thickness of the rubber band when looking at it from above.
• To get the thickness of the rubber band, you will have to carefully lift the rubber band in between your fingers and measure the wall’s thickness from the side.

So, when looking at a Size 117B rubber band, you should get the following measurements:

• Flat Length = 7 inches
• Width = 1/8 of an inch
• Wall Thickness = 1/32 of an inch

What Other Factors Should I Consider When Buying Rubber Bands?

If you want to be technical about it, you should consider the following variables.

Ultimate Elongation—How long you can stretch the rubber band until it snaps (expressed in percentages). A higher ultimate elongation figure means that the rubber band can stretch to several times its original size before the walls begin to thin out.

Permanent Set—How much longer the rubber band will become after stretching it to its ultimate elongation and returning to its normal, unstretched state (expressed in percentages). A higher permanent set figure means that a stretched rubber band will be much longer than its original length.

Specific Gravity—A ratio figure that describes the density of the rubber band to the density of water. A lower specific gravity figure could mean that the rubber band has fewer fillers and is of higher quality.

Durometer—A figure that describes the hardness of substances like rubber and plastic. The higher the durometer figure is, the harder and less resistant to snapping it becomes.

So, what do these figures mean for someone who wants to use rubber bands for basic arts and crafts projects? Not much—they’ll only come in handy when you need rubber bands for industrial purposes. However, you might want to pay attention to the ultimate elongation rating if you use rubber bands to keep larger objects together.

Does Rubber Band Size Matter?

The size of a rubber band will only matter when you want to use it to organize large objects—e.g., keeping books together, using rubber bands to shut a laptop, etc.

For instance, let’s compare Sterling Size 117A to Sterling Size 32 rubber bands. They are both made of the same materials and have the same ratio of fillers to rubber. As such, they come with the same ultimate elongation rating of 750%.

Using the size chart above, a Size 117A rubber band can stretch to 750% over 7 inches or up to 52.5 inches, whereas Size 32 rubber bands are limited to just 22.5 inches. Basically, you could double-coil a Size117A rubber band around the largest object that a Size 32 rubber band can hold in place.

However, when it comes to tying smaller objects together, the fewer times you’ll have to loop the same rubber band, the easier it will be to remove from the object in the future, thus making Size 32 rubber bands more ideal than Size 117A in these situations.

What Are Rubber Bands Made of?

A rubber band can be made of 3 different materials—rubber, synthetic rubber, or silicone.

• Rubber bands were originally made with authentic rubber tapped from rubber trees. It is a highly elastic material that’s also durable, allowing it to stretch to several times its original size without tearing or snapping.
• Synthetic rubber bands, which also go by the moniker “non-latex rubber bands,” are rubber bands that have the latex proteins removed. Latex is a common allergen that can lead to skin irritation. While synthetic rubber bands can stretch and have a decent snap, they’re not as durable as natural rubber.
• Despite its name, silicone rubber bands do not contain any rubber at all. Silicone is a plastic polymer that imitates the elasticity of rubber. It is much more durable, but it does not stretch nearly as far as traditional rubber.