String tension is the force pulling a guitar string tight between the nut and bridge. It depends on string gauge (diameter), scale length, and tuning frequency. Understanding tension helps you choose the right gauge for drop tunings, custom setups, or instrument modifications.
String Parameters
Standard electric: .009–.013. Acoustic: .011–.014. Bass: .040–.065
Fender: 25.5" · Gibson: 24.75" · Baritone: 27" · Bass: 34"
Tension Level
Enter parameters and click Calculate
Standard Guitar String Set Tensions
| Set | Gauges | Total Tension (lbs) | Feel |
|---|---|---|---|
| Extra Light | .009–.042 | ~98 lbs | Easy bending, less volume |
| Light | .010–.046 | ~107 lbs | Standard electric guitar balance |
| Medium | .011–.049 | ~120 lbs | More volume, harder to bend |
| Heavy | .013–.056 | ~143 lbs | Maximum tone, stiff feel |
How to Use the String Gauge Tension Calculator
This string tension calculator uses the physics formula T = (UW × (2 × L × F)²) / 386.4 to calculate the pulling force a string exerts on a guitar neck. Understanding tension helps you choose gauges for alternate tunings and custom setups.
Choosing Gauges for Drop Tunings
Drop tuning reduces string tension, making strings feel loose and reducing sustain. As a rule of thumb, increase gauge by 0.001" for each semitone you drop. For Drop D (.010 high E set): the low E drops one semitone, so consider using .011 for that string, or a hybrid set. For B standard (3.5 steps down), consider .012–.056 or heavier.
Scale Length and Tension
Longer scale lengths create higher tension for the same gauge and tuning. A .010 string at E4 on a 25.5" Fender scale has about 16.2 lbs tension. On a 24.75" Gibson scale, the same string has about 15.4 lbs — about 5% less. This is why Gibson's "medium" (.011) sets feel comparable to Fender's "light" (.010) sets.
FAQ
Is this string tension calculator free?
Yes, completely free. Calculate string tension for any gauge and tuning without any account or payment.
Is my data private?
All calculations run in your browser. No data is sent to any server.
How is string tension calculated?
String tension uses the formula T = (UW × (2 × L × F)²) / 386.4, where UW is unit weight in lbs/inch, L is scale length in inches, and F is frequency in Hz. The unit weight is determined by the string's mass per unit length, which depends on the gauge and core material.
What is a comfortable string tension?
Most guitarists prefer 12–17 lbs per string for electric guitar, 16–20 lbs for acoustic, and 30–40 lbs per string for bass. Total neck tension for a standard 6-string electric is typically 80–120 lbs. Higher tension gives more volume and sustain but harder playability.
Does scale length affect tension?
Yes. Longer scale lengths increase tension for the same gauge and tuning. A .010 string on a 25.5' (Fender) scale is under more tension than on a 24.75' (Gibson) scale. Drop-tuning guitars often use heavier gauges to compensate for lost tension.
How does tuning to Drop D or lower affect tension?
Dropping the low E to D reduces tension on that string by about 20–25%. This makes the string floppy and reduces sustain. Using a heavier gauge for dropped strings (e.g., .013 instead of .010 for the low string) restores tension and playability.
What gauge should I use for B standard tuning?
For B standard tuning (all strings down 2.5 steps from E standard), many guitarists use .012–.056 or .013–.060 sets. The exact gauge depends on your scale length and preferred feel. This calculator helps you find the tension for any specific combination.