Guitar String Tension Calculator
Calculate string tension in pounds and kilograms from gauge, scale length, and tuning.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Guitar String Tension Calculator
Enter your string gauge, scale length, and target tuning frequency to calculate the tension that string will exert on your guitar neck and bridge.
- Select a tuning preset to fill in the frequency automatically, or enter a custom frequency in Hz. Standard E4 (high E) is 329.63 Hz. A4 (standard concert pitch) is 440 Hz.
- Enter the string gauge. Type the gauge in thousandths of an inch. A .010 string = 10, a .046 = 46. Plain steel strings and wound strings use different unit weight tables, so actual tension for wound strings is approximate.
- Set the scale length. Use 25.5 for Fender-style guitars, 24.75 for Gibson-style, 34 for standard bass. Longer scale = higher tension at the same pitch.
- Read the tension. The result shows tension in pounds and kilograms, plus a qualitative feel rating (very light, light, medium, heavy, very heavy) based on typical player preferences.
About String Tension
String tension determines how hard a string feels to fret and bend. The formula is T = UW * (2 * L * F)^2 / 386.4, where UW is the unit weight of the string in pounds per inch, L is the scale length in inches, and F is the frequency in Hz. The constant 386.4 converts inches per second squared to standard gravity units.
Most players find single strings comfortable between 13 and 20 lbs of tension. Full sets across six strings generate 100 to 180 lbs of total neck load. When down-tuning (drop D, Eb, D standard, C standard), heavier gauges are often used to maintain similar tension and feel. When up-tuning or using a longer scale (baritone), lighter gauges help keep tension manageable.
Frequently Asked Questions
What string gauge should I use for drop tuning?
When you tune down, tension drops and strings feel slack and buzzy. As a rough guide, each half step down requires roughly 6-7% heavier gauge to maintain the same tension. For drop D (one whole step down on the low string), going from a .046 to a .052 or .054 keeps the tension similar. For full-step-down D standard, moving from .010-.046 to .011-.049 or .011-.052 is common. This calculator lets you compare different gauges and frequencies directly to find the right match.
How does scale length affect string tension?
Tension scales with the square of the scale length. Going from a 24.75-inch Gibson scale to a 25.5-inch Fender scale increases tension by about 6% at the same pitch and gauge. A 27-inch baritone scale at the same pitch and gauge has roughly 22% more tension than a standard 25.5. This is why baritone guitars typically use lighter gauges or lower tunings, and why short-scale basses (30 inches) feel significantly easier to play than standard 34-inch basses strung with the same gauge.
What is a comfortable string tension range?
Most electric guitar players find individual string tension between 13 and 20 lbs comfortable for standard playing. Classical guitarists and fingerpickers often prefer 8 to 12 lbs on plain strings. Bass strings typically run 30 to 55 lbs per string. Very light tension (below 10 lbs on guitar) can feel loose and cause intonation issues. Very high tension (above 25 lbs) increases fretting effort and bending difficulty. The ideal tension is personal and also depends on the instrument's neck relief and action height.
Why do wound strings have different tension than plain strings at the same gauge?
A wound string has a thin steel core wrapped with nickel, bronze, or other wire. The winding adds mass without adding proportional stiffness the way a plain steel string would at the same outer diameter. This means a wound .046 string has a different unit weight than a plain .046 string, so the tension calculation differs. String manufacturers publish unit weight (pounds per linear inch) for each string in their lineup, and this calculator uses empirical approximations based on D'Addario tension charts for common gauges.