Bass
Fan
Treble
Perp
Multi
Pocket Roady Tool Stack Deluxe
Power
Multi-Scale Plotter

Design your fan-fret neck.

Multi-scale fan-fret guitar neck showing fanned fret lines

Set your bass and treble scale lengths, pick a perpendicular fret, and see the fan geometry with per-string tension balance.

Fan-fret geometry — to scale
# Scale Nut offset Bridge offset Tension
Overall feel
🎸 What the Perpendicular Fret Does
The perpendicular fret is the one fret that runs perfectly straight across all strings — the others fan outward from it. Lower numbers (closer to the nut) produce a more aggressive fan angle; higher numbers produce a subtler one. Most builders pick 7, 8, or 9 as a comfortable middle ground where the fan feels natural under the fretting hand.
Fan-fret multiscale guitar fretboard showing angled frets
🎸 Why the Bass Side Gets More Scale
Longer scale on the bass strings means more tension at the same pitch and gauge — which is exactly what keeps those low strings tight and defined instead of floppy. The per-string tension table above shows the balance your design actually produces, string by string.
Design visualizer, not a build file. These are ideal theoretical positions. Before cutting, confirm all dimensions against your own shop tools and templates. Strings are modelled as evenly spaced and parallel — the standard simplification for fan-fret geometry.

Want to go deeper on the tension numbers, or look up exact fret positions for a single scale? The engines behind this tool are also standalone calculators.

String Tension Calculator → Fret Position Calculator →