Guitar String Tension Calculator
String tension determines how your guitar feels and sounds. A .046 low E string on a 25.5" Fender scale at standard tuning pulls about 17.5 lbs of force. That same string on a 24.75" Gibson scale pulls about 16.4 lbs, which is why Gibson-scale guitars feel slinkier. This calculator uses the standard D'Addario-style tension formula to help you dial in your perfect setup.
The string tension formula is:
T = (UW * (2 * L * F)2) / 386.4
- T = tension in pounds
- UW = unit weight of the string in lb/in
- L = scale length in inches
- F = frequency in Hz
- 386.4 = gravitational acceleration in in/s2
Common Unit Weights (lb/in)
| Gauge | Plain | Wound |
|---|---|---|
| .009 | 0.00001517 | - |
| .010 | 0.00001874 | - |
| .011 | 0.00002267 | - |
| .024 | - | 0.0001055 |
| .032 | - | 0.0001854 |
| .042 | - | 0.0003178 |
| .046 | - | 0.0003747 |
| .052 | - | 0.0004808 |
Most guitarists are comfortable with per-string tension between 14 and 22 lbs. Below 12 lbs feels floppy; above 25 lbs feels very stiff. When switching to alternate tunings (like Drop D or Drop C), you typically need heavier gauges to maintain adequate tension and avoid a muddy tone.