Guitar String Tension Calculator
Musicians and luthiers use this guitar string tension calculator to determine the amount of force exerted by a string on a guitar’s neck and bridge.
By inputting variables such as scale length, string gauge, and tuning frequency, the calculator provides an accurate estimation of string tension.
Consider a standard electric guitar with a 25.5-inch scale length, using a .046 gauge low E string tuned to 82.41 Hz (E2). The string tension calculator factor in these parameters to determine that this string exerts approximately 16-18 pounds of tension on the instrument.
Guitar String Tension Chart
| String | Gauge (inches) | Frequency (Hz) | Scale Length (inches) | Tension (lbs) |
|---|---|---|---|---|
| Low E | .046 | 82.41 | 25.5 | 16.5 |
| A | .036 | 110.00 | 25.5 | 16.2 |
| D | .026 | 146.83 | 25.5 | 15.8 |
| G | .017 | 196.00 | 25.5 | 13.1 |
| B | .013 | 246.94 | 25.5 | 12.6 |
| High E | .010 | 329.63 | 25.5 | 14.7 |
Guitar String Tension Formula
The formula for calculating guitar string tension is:
T = (UW x (2 x L x F)^2) / 386.4Where:
- T = Tension in pounds
- UW = Unit Weight of the string (pounds per inch)
- L = Scale Length (inches)
- F = Frequency (Hz)
Let’s calculate the tension for the low E string from our example:
UW for a .046 gauge string ≈ 0.0000992 lbs/inch
L = 25.5 inches
F = 82.41 Hz
T = (0.0000992 x (2 x 25.5 x 82.41)^2) / 386.4 T ≈ 16.5 lbsHow do you calculate string tension on a guitar?
To calculate string tension:
Find the unit weight of the string (usually provided by manufacturers)
Measure the scale length of your guitar
Identify the frequency of the desired pitch
Apply these values to the formula: T = (UW x (2 x L x F)^2) / 386.4
For instance, calculating tension for a .013 gauge B string (246.94 Hz) on a 25.5″ scale guitar:
UW ≈ 0.0000228 lbs/inch
L = 25.5 inches
F = 246.94 Hz
T = (0.0000228 x (2 x 25.5 x 246.94)^2) / 386.4 T ≈ 12.6 lbsRelated Music Tools