// Precision fret spacing
Multiscale · Any temperament · CNC-ready
Exact fret positions for any instrument, scale length or temperament. Printable PDF templates and 1:1 DXF files for CAD/CAM.
// Setup
The longer scale sets the fan direction — enter a shorter bass scale for a reversed (left-handed) fan.
0° = perpendicular bridge. Measured across the string spread at the bridge.
12 = standard chromatic. Try 17, 19, 24, 31…
Fretboard edges
Diagram layers
Proportional schematic — not 1:1. Use PDF / DXF exports for true size.
Print at 100% scale — disable "fit to page". Verify the calibration rectangle with a ruler before using as a template.
// Measurements
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// Knowledge
Fret positions follow the equal-temperament formula: distance from nut = scale length × (1 − 2^(−n/EDO)), where n is the fret number and EDO the divisions per octave (12 on a standard guitar). Each fret shortens the vibrating string by a ratio of 2^(1/EDO), so every 12 frets (EDO 12) the octave falls exactly at half the scale. This calculator uses the exact formula with no rounding or compensation.
On a fanned-fret instrument every string has a different scale length, so frets slant across the fingerboard. The perpendicular fret is the one that sits at 90° to the centerline — the pivot of the fan. Frets above it slant one way, below it the other. Pick it in this calculator and the nut and bridge angles are derived automatically; or enter a bridge angle directly and the perpendicular fret is calculated for you.
Common multiscale pairs: 25.5"–27" for 6-string drop tunings, 26"–28.5" for 7-strings, 26.5"–29" for 8-strings. Longer bass scales keep low strings tight and clear; shorter treble scales keep high strings comfortable to bend. The difference is typically 1.5"–3".
EDO = equal divisions of the octave. Standard guitars are 12-EDO (12 semitones per octave). This calculator accepts any EDO: 17, 19, 24 (quarter-tones), 31 and beyond — just change "divisions per octave". Fret positions are computed with the same exact formula.
These are exact theoretical positions — sharp strings at the first frets are normal and are corrected at the bridge with intonation (saddle setback, typically 2–6 mm beyond scale length on electric guitars). Measure fret slots with this table; place your bridge/saddle compensation separately per string.
Yes. The template pages print at true 1:1 (print at 100%, disable "fit to page") and include a calibration rectangle to verify your printer's scaling with a ruler. The DXF is drawn at 1:1 in your selected units on separate layers (outline, fret slots, nut, saddle) — import it into Fusion 360, VCarve, AutoCAD, InkScape or laser software and cut directly.
100% free, no registration, no limits, works on mobile and desktop. Everything runs in your browser — your measurements never leave your computer. If it saves you time, the "buy me a guitar pick" donation keeps the workshop running.