🎼 Guitar String Tension Calculator
Estimate the pull tension of a guitar string from its gauge, scale length, target pitch, and material.
How string tension is calculated
A guitar string’s tension depends on how thick and dense it is, how long the vibrating portion is (scale length), and what pitch it’s tuned to. This calculator uses the standard string-tension formula used by string manufacturers.
Formula used: Tension (lbs) = Unit Weight × (2 × Scale Length × Frequency)² ÷ 386.4, where Unit Weight is the string’s weight per inch, calculated from its diameter and material density as Unit Weight = Density × π × (Diameter ÷ 2)². The constant 386.4 converts the result into pounds using standard gravitational acceleration in inches per second squared.
- Enter the string’s gauge (diameter) in inches, as printed on most string packaging.
- Enter your guitar’s scale length (nut to bridge) in inches.
- Enter the target note’s frequency in Hz (for example, standard tuning B on the 2nd string is 246.94 Hz, and standard tuning B on the 3rd string is 329.63 Hz for high E).
This tool gives estimates for general instrument setup and educational purposes; actual tension can vary by string manufacturer and construction.