Bass string spacing
Fender's HiMass 4-string bridge spaces the saddles 0.75″ (19.05 mm) apart, so the E and G sit 2.25″ (57.15 mm) apart, center to center. The American Professional II Jazz Bass has a 1.5″ (38.1 mm) nut and the Precision Bass a 1.625″ (41.3 mm) one. Graph Tech's Jazz Bass nut puts the E and G 31.3 mm (1.23″) apart.
Bass string positions
Each string's position from the center of the E, with an equal clear gap between strings: 57.15 mm at the bridge, 31.3 mm at the nut, D'Addario EXL170.
| String | Gauge | Bridge (mm) | Nut (mm) |
|---|---|---|---|
| 4 | .100 | 0.00 | 0.00 |
| 3 | .080 | 19.49 | 10.88 |
| 2 | .065 | 38.54 | 21.31 |
| 1 | .045 | 57.15 | 31.30 |
Fender — HiMass 4-String Bass Bridge Assembly (.75″ string spacing)
How to use it
- Choose bridge or nut; 57.15 mm or 31.3 mm fills in. For a P Bass nut, enter your own measurement.
- At the nut, keep Equal gap: with gauges from .045 to .100 the difference shows. At the bridge, switch to Equal centers to match fixed saddles.
- In the radius section, pick 9.5″ and read the arc at each fret.
Help and explanations
Those numbers and a D'Addario EXL170 (.045–.100) set are loaded. The table shows each string at the bridge and the nut; the radius section covers 7.25″, 9.5″ and 12″ boards on a 34″, 20-fret neck.
Equal gap or equal centers on a bass
Bass strings vary a lot in size: the .100 E is 2.54 mm thick, the .045 G 1.14 mm. With 31.3 mm between the outer strings at the nut, equal centers would leave 8.15 mm of clear space next to the E and 9.04 mm next to the G. Equal gap evens it out at 8.59 mm, with centers 10.88, 10.43 and 9.99 mm apart. A 38.1 mm Jazz nut then leaves 2.48 mm from each outer string to the edge.
Fender's fixed 0.75″ saddle spacing is equal centers: 16.76 mm clear next to the E and 17.65 mm next to the G. Players who want wider or narrower spacing go for a bridge with adjustable saddle positions.
Radius on a 34″ neck
Fender lists a 9.5″ (241 mm) radius on the American Professional II Precision and Jazz Bass. Across a 1.5″ nut that's 0.75 mm of arc in the middle; a 7.25″ board would rise 0.99 mm. The bridge saddles are set to the same curve, so the A and D saddles sit higher than the E and G.
The board widens toward the body, so the arc grows along the neck. Fender doesn't publish the width at the last fret; measure yours and enter it to see the arc at each fret and print a radius gauge.
Tips
- Bass strings are thick enough to throw an edge-to-edge reading off by 1.84 mm with an EXL170 (half of .100 plus half of .045), so always work center to center.
- After a nut or bridge change, reset the bass action.
- Going to heavier strings? Nut slots may need widening; compare sets in the string tension calculator.
Frequently asked questions
What is the string spacing on a Fender bass bridge?
0.75″ (19.05 mm) between neighboring saddles on the HiMass bridge, so 2.25″ (57.15 mm) between the E and G.
What is the nut width of a Jazz Bass?
1.5″ (38.1 mm) on the American Professional II Jazz Bass. The Precision Bass is wider: 1.625″ (41.3 mm).
What is Jazz Bass string spacing at the nut?
Graph Tech's Jazz Bass nut spaces the E and G 31.3 mm (1.233″) apart, about 10.4 mm from string to string.
What fretboard radius does a Fender bass have?
9.5″ (241 mm) on the American Professional II Precision and Jazz Bass.
How do I measure bass string spacing?
Center to center of the outer strings. If you measure from outside edge to outside edge, subtract half of each outer string's gauge.