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How To Measure Compound Bow String Length

There is no single answer to the question of how long your compound bow string should be. However, the measurement of bow string length is integral to archery. It allows archers to get the most accurate shots possible. That's why you must know how to measure compound bow string length!

Ultimately, it is up to the archer to decide which method works best for them. So, be sure to take the time to measure your bowstring length accurately, and you'll be on your way to becoming a better shot!

You may determine the length of a compound bow string in one of two ways. One is the "AMO Method," while the other is the "manual way." Check them out:

Method 1: Manually

First, let's try doing it by hand. Manually gauging the length of a compound bow's string is more complex than with a recurve. To do the math, you need to know a secret.

The length of a compound bow string is determined as the bow is being stretched.

The conventional method for attaining such a state is producing a strain of 100 lbs. by putting loops around the 14 inches diameter pin on the Top limbs. A bow press is a helpful instrument for this purpose.

The dimensions are shown as the distance between the pins.

These are the most straightforward steps if you want to determine string length for your compound bow.

Step 1: The bow press is where you'll put your compound bow.

Step 2: Bow and push it down with 100 pounds of pressure.

Step 3: Put a dot on the string to indicate where it should be cut.

Step 4: It's time to take some measurements.

You may consider that problem solved.

Method 2: AMO Method

This measurement system is likely more convenient than traditional methods. Although this technique of measuring a compound bow is not quite as simple as the previous one, it is still significantly more superficial than the recurve approach.

The most significant difficulty with this technique is that compound bows don't often have the AMO Length clearly defined. Let's figure out how to use this method of measuring length.

  • First, put the bow on its back.
  • Measure the arc of the bow's limbs from one string groove to the next.
  • Stay away from the grip region and instead go along the bow's natural line, often known as its belly.

String length, weight, cable, and draw all contribute to the AMO level of a compound bow. These estimates are often quite close to the proper size. You can use a bow string length calculator in this process.

If you know the draw weight but not the length, you may measure the Draw length to determine the size of your string.

How Long Should A Bow String Be?

For optimal performance with a recurve bow, the string should be roughly 3.5 inches shorter than the bow. For example, a 68-inch bow requires a string length of approximately 64 and a half inches.

Determine its size by counting the number of string grooves along its length. Finding the length of your bowstring requires knowing the length of the bow itself.

When shooting a recurve, the bowstring is typically 4 inches shorter than the whole length of the bow.

The bowstring for a longbow is three inches shorter.

Why Should You Perfectly Measure Compound Bow String Length?

Compound bows are a great way to shoot a bow, but they can be more challenging if the bowstring is not correctly measured. However, you can get the most out of your shooting experience with the right bowstring length.

There are many reasons why you should perfectly measure the length of your compound bow string. Here are just a few:

  • If the string is not tensioned correctly, it can cause your bow to malfunction and become inaccurate.
  • A poorly tuned bow can also cause you to miss your target or injure yourself.
  • Correctly measuring the string's length ensures that it works properly and in harmony with the rest of your bow setup.
  • You will get better accuracy with your shots.
  • You can hold your shots longer and shoot more repeatable groups.


Measuring your bowstring length correctly is essential to ensure accuracy and precision while shooting.

There are a few methods to measure your bowstring length, and each has its benefits and drawbacks.

We hope this step-by-step definitive compound bow string guide will be convenient for your archery.

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