How the guitar string tension calculator works
String tension is the pulling force a string puts on the neck when it is tuned to pitch. You feel it every time you bend a note or dig into a riff. Too little tension and strings flop and buzz. Too much and bends get hard, the neck bows forward, and thin strings break more often.
Inputs
- Instrument and tuning.Electric guitar or electric bass, with presets from standard to Drop A, DADGAD, and open tunings. You can also change any single string's pitch.
- Scale lengthin inches or millimetres, from 15" to 40".
- Gauge and constructionfor every string, plain or wound. The "Regular set" and "Heavy set" buttons load 10-46 and 11-52 for guitar.
- Material.Estimates assume steel. For bronze, nickel, or brand-specific construction, turn on "Manufacturer unit weights" and enter the value from the string maker's chart.
Outputs
- tension for each string in pounds, kilograms-force, or newtons, with a bar so you can spot outliers
- total tension for the whole set
- a side-by-side comparison: press "Capture comparison", change the set, and the table shows the change per string and the total percentage change
Under the hood it uses the standard formula, T = UW × (2 × L × f)² / 386.4, where UW is unit weight, L is scale length, and f is the string's frequency at A4 = 440 Hz.
Why guitarists use a tension calculator
Planning a gauge swap without losing the feel
Going from 10s to 11s sounds like a small step. The calculator shows it is about 15% more total tension, which is enough to change how bends feel and to need a truss rod tweak. Capture your current set, load the new one, and you see the difference before you buy strings.
Checking drop and low tunings
Every semitone you tune down removes about 11% of a string's tension. A 10-46 set in Drop C is down to about 79 lb total, and the low C string sits near 11 lb, which is why it flaps. Loading the 11-52 heavy set brings the total back near 98 lb, close to where 10-46 sits in standard. Our Drop C tuning guide and Drop D muddy-sound fixes go deeper on string choice for low tunings.
Balancing tension across a hybrid set
Off-the-shelf sets are not perfectly even. Mixing single strings from different packs lets you smooth out a loose G or a stiff high E. The per-string bars make the uneven string obvious at a glance.
Example scenarios
All numbers below come from this guitar string tension calculator with its default steel estimates. Brand charts will differ slightly on the wound strings.
Standard E with 10-46 vs 11-49 on a 25.5" scale
| String | 10-46 gauge | Tension | 11-49 gauge | Tension |
|---|---|---|---|---|
| E4 (high) | .010 | 16.3 | .011 | 19.7 |
| B3 | .013 | 15.4 | .014 | 17.9 |
| G3 | .017 | 16.6 | .018 | 18.6 |
| D3 | .026w | 17.9 | .028w | 20.7 |
| A2 | .036w | 19.2 | .038w | 21.4 |
| E2 (low) | .046w | 17.6 | .049w | 20.0 |
| Total | 103.0 | 118.3 (+15%) |
Every string gains 2 to 3.5 lb. The high E gains the most, which is why bends on the first string are the first thing people notice after moving up to 11s.
Drop D on a 24.75" guitar: tension change per string
With a 10-46 set on a 24.75" scale, standard tuning totals about 97 lb. Tuning the sixth string down to D drops that string from 16.6 lb to 13.2 lb, a 20% loss, while the other five strings do not change at all. The total only falls to 93.6 lb, but the low string now feels noticeably looser than the A string next to it (18.1 lb).
Swap that one string for a .049 and it comes back to 15.0 lb, which evens out the feel without buying a whole new set. For comparison, the same Drop D on a 25.5" neck leaves the low D at 14.0 lb. More on the tuning itself in our Drop D tuning guide.
Balancing a custom set: high E from set A, others from set B
Say you like the thick low end of an 11-49 set but find its .011 high E too stiff for bends. Take the high E from a 10-46 set instead:
| Setup | High E | B | Total |
|---|---|---|---|
| Stock 11-49 | .011 · 19.7 lb | .014 · 17.9 lb | 118.3 lb |
| 11-49 with .010 high E | .010 · 16.3 lb | .014 · 17.9 lb | 114.9 lb |
The high E loses 3.4 lb and now sits just below the B string instead of well above it, so bends on the top two strings feel similar. The low strings keep all their punch.
Tension alone does not tell you whether a setup is safe or comfortable. Neck relief, action, and your own hands matter too. If you make a big change, check the setup afterwards; our guitar intonation guide walks through it.
Guitar string tension FAQs
What is a good total tension for electric/acoustic?
On a 25.5" electric in standard tuning, this calculator puts a 9-42 set at about 84 lb, 10-46 at about 103 lb, and 11-49 at about 118 lb. Most players land somewhere in that band. Light 12-53 acoustic sets are usually quoted around 160 lb. There is no single right number: what matters is that each string feels similar under your fingers and your truss rod can hold the neck straight.
Does scale length affect tension?
Yes, and more than people expect. Tension rises with the square of the scale length. The same 10-46 set in standard tuning drops from about 103 lb on a 25.5" Fender-style neck to about 97 lb on a 24.75" Gibson-style neck, roughly 6% less. That is why the same gauges feel slinkier on a Les Paul than on a Strat.
Can I use this for bass or other instruments?
Yes for electric bass. Switch Instrument to Electric bass, set 4, 5, or 6 strings through the tuning menu, and enter your scale length (34" is the default). It works as a bass string tension calculator for any steel-string setup. It is not built for nylon strings, so classical guitar and most ukulele sets will give wrong numbers.
How accurate are the tension numbers?
Plain strings are close to published charts, usually within a few tenths of a pound. Wound strings are estimates, because every brand uses a different core and wrap. For exact numbers, tick "Manufacturer unit weights" and type in the unit weight from the string maker's chart.
Is lower tension bad for my guitar?
Lower tension is not dangerous, but it can cause fret buzz, a floppy feel, and tuning that wobbles when you pick hard. Higher tension than the neck was set up for can add relief and raise the action. After a big change in either direction, check your neck relief and intonation.