What Size Is A Standard Tow Ball Hitch? (And How To Measure It)

Ball hitches are essential towing accessories. More importantly, you'll need the correct ball hitch to tow safely and legally, too. Fortunately, figuring out which size ball hitch you need is a straightforward task, and there are a series of standard sizes to choose from.

For the majority of applications, a 2-inch tow ball hitch is the go-to. Typically, it supports medium-duty towing needs, with a general weight capacity of up to 8,000 pounds. This means a 2-inch tow ball hitch is ideal for towing smaller boats, campers, or single-vehicle trailers, including a smattering of other loads. If you're planning on towing a lighter load, something like a jet-ski or small motorcycle, then perhaps a 1-⅞-inch tow ball hitch will suffice. This is the smallest standard-size tow ball hitch, and it can handle up to 2,000 pounds of gross trailer weight. For the occasional tower who never has to pull anything heavier, a 1-⅞-inch tow ball hitch is perfect.

If, however, towing needs surpass what the two aforementioned sizes can handle, then stepping up to the largest standard size tow ball hitch is recommended. This means installing a 2-⁵⁄₁₆-inch tow ball hitch, which is capable of working with weights which can go over 10,000 pounds, and even three times that amount in certain applications. A hitch of this size is usually best-suited to full-size SUVs and pickup trucks, as a larger, more powerful vehicle is generally required in order to tow loads of this size.

Your vehicle may already have a towing setup installed, which is great, as it saves you splashing out on buying a new one. However, it's essential you verify what size tow ball hitch is installed to ensure it's the correct choice for your needs to safely tow your trailer or camper. First, inspect the hitch for any markings — it may be marked up with the size, which would save you from physically measuring it.

If no clear markings are present, or you simply want to double-check the size, then measuring the diameter is how to accurately determine the tow ball hitch size. Simply grab a tape measure and take a reading of the ball's circumference at its center. To calculate the diameter from a circumference reading, just divide the reading by Pi (3.1416). An example would be 5.89 (circumference reading in inches) divided by Pi, giving you 1.875 as the result. With 1.875 equating to 1-⅞ inches, this sum establishes the ball hitch size.

If math is not your strong suit, it can be easier to just measure the tow ball hitch size using a vernier caliper. Simply hook the tool over the ball hitch at its widest point and take the reading — this will provide you with the size. Once you've found the perfect fit, you can try out one of these great tow hitch add-ons too.