Guitar String Tension Calculator

This guitar string tension calculator will help you choose strings for your guitar while keeping string tension in mind. Knowing some basic guitar string tension physics can help you learn how to calculate guitar string tension, understand your instrument more, and create a more comfortable playing experience, suitable for beginners.

In this calculator, you will learn:

• How to calculate guitar string tension;
• Some basic guitar string tension physics - the factors in tuning a guitar;
• What the guitar string tension formula is; and
• Some basic information about balanced tension guitar strings.

Ready to learn how much tension is on your guitar strings? Then, let's get started.

The guitar string tension is one of these three factors that influence the frequency of a guitar string, along with the string gauge and guitar's scale length. Thinner strings weigh less and can vibrate faster than thicker strings, resulting in higher-pitch sounds. Guitar strings are available in gauges as thin as 0.007th of an inch to as thick as 0.08th of an inch.

We can purchase guitar strings in materials like steel, nickel, copper, and nylon. We quantify their weight using linear density, also commonly called unit weight. We usually express this measurement in pounds per inch or kilograms per meter. Thicker strings require more tension or a heavier pull to achieve their required tuning.

Now, let's look at the guitar's scale length. The scale length is the length of the open string between the guitar's nut and bridge and is the length over which the string vibrates to produce a sound. A long scale length would require more tension to pull a string tight to meet its desired pitch. The same string would require less tension to be tuned to that same pitch if it was placed on a shorter scale length. A shorter scale length doesn't limit a guitar's music scale. However, it can affect the size of each fret of the guitar.

Applying more tension to a particular string gauge than it's meant to handle would produce a higher pitch and may cause it to snap. Applying less tension results in a looser string which produces a lower pitch. Sometimes, however, even at the correct tension, it feels hard to press the string down the guitar's fingerboard, even resulting in discomfort or pain.

Through experience, you will learn which string gauges feel okay to you while you play. You can then use that as a reference when choosing replacement strings for your guitar. To get the right strings for you, we need to learn some guitar string tension physics. That is where our guitar string tension calculator comes in handy.

With our guitar string tension calculator, you will find the tension through a particular guitar string. Once you know that string's tension, you can use that as a reference when choosing a string gauge for your other strings. Here are the steps you can follow when using our calculator:

1. Enter your guitar's scale length.
2. Select the pitch of your string to match your preferred tuning.
3. Choose the string type and string gauge you want to use. Doing so will display the required tension for this string.

As an added feature to this tool, you can also use our guitar string tension calculator as a guitar string unit weight calculator. Simply repeat these same steps and replace the estimated tension with your desired guitar string tension. Our tool will then recalculate the recommended unit weight for that tension and frequency. This is perfect if you already know how a particular string tension feels to your finger.

In this section, you will learn how to measure the guitar string tension using this very simple guitar string tension formula derived from the wavelength formula:

where:

• $T$ – Guitar string tension;
• $f$ – Frequency the string vibrates at;
• $L$ – Scale length;
• $\mu$ – Linear density or unit weight of the string; and
• $g$ – Gravitational acceleration.

Naturally, we measure tension in units such as pound-force or Newtons and don't have the gravitational acceleration in the formula. But, in some cases (like in the string tension of a bowstring or tennis racquet strings), we express tension in terms of mass. In the next section, let's use this formula to find how much tension is on a guitar string.

Let's say we want to determine the tension needed to pull a 0.010-gauge pure steel string, with a unit weight of $\small 0.00002215\ \text{lb}/\text{in}$, to tune it to E4 on a $\small 25.5\ \text{in}$ scale length guitar. Ideally, E4 vibrates at a rate of $\small 329.6\ \text{Hz}$. Using our guitar string tension formula, we now have:

With our guitar string tension calculator, you can now try out different string gauges for your other strings and try to get values close to 16.2 lb. That will ensure you have balanced tension guitar strings. Typically guitar strings are available in sets that result in a variety of string tensions, but some stores sell balanced tension guitar strings if that's what you want.

If you found this interesting and would like to learn more about guitar physics, you can check out our fret calculator. There you will learn how to calculate the placement of frets and how its formula is derived.