🎸 Guitar String Tension Calculator
Enter the scale length, string gauge and material to compute each string's tension in newtons, pounds-force and kilogram-force plus its linear density, using the physics of a vibrating string. Standard tunings and a custom frequency are supported — handy for string selection, setup and lutherie.
Standard tuning frequency reference
| Note | Frequency (Hz) | Description |
|---|---|---|
| E2 | 82.41 | Standard 6th string, lowest |
| A2 | 110.00 | 5th string |
| D3 | 146.83 | 4th string |
| G3 | 196.00 | 3rd string |
| B3 | 246.94 | 2nd string |
| E4 | 329.63 | 1st string, highest |
Equal temperament, A4 = 440 Hz. Frequency is the fundamental pitch and scales with the square root of tension.
How is guitar string tension calculated?
From the fundamental frequency of a vibrating string f = (1/2L)·√(T/μ), solving for tension gives T = (2Lf)²·μ. L is the scale length (m), f is the pitch frequency (Hz), and μ is the linear density (kg/m) derived from material density and gauge: μ = ρ·π·(d/2)².
What tension is normal?
On a steel-string acoustic guitar a single string usually runs 10–20 lbf (about 45–90 N); a full six-string set totals roughly 150–180 lbf. Too high causes buzzing and neck strain, too low feels loose and goes out of tune easily.
How do material and gauge affect tension?
At the same tuning and scale length, a thicker gauge or denser material raises linear density μ and therefore tension. Switching to a thinner string or low-density material like nylon lowers tension noticeably — which is why classical guitars feel lighter than steel-string guitars.
Are the results theoretical or measured?
This tool returns the ideal uniform-string theoretical value assuming a homogeneous round cross-section with perfectly fixed ends. Wound strings, temperature and string age cause small deviations, but it is reliable for string selection, setup and lutherie reference.