Fret Calculator
Calculate precise fret positions for guitar building and luthiery using scale length
Calculate Fret Positions
Distance from nut to bridge (saddle)
Typically 12-24 frets for guitars
Fret Position Formula
Distance from nut: L₀ × (1 - (0.9438743)ⁿ)
Distance from bridge: L₀ ÷ (1.0594631)ⁿ
Where L₀ is scale length and n is fret number
Fret Positions
| Fret | Distance from Nut (inches) | Distance from Bridge (inches) | Note |
|---|---|---|---|
| 1 | 1.431 | 24.069 | C |
| 2 | 2.782 | 22.718 | C# |
| 3 | 4.057 | 21.443 | D |
| 4 | 5.261 | 20.239 | D# |
| 5 | 6.397 | 19.103 | E |
| 6 | 7.469 | 18.031 | F |
| 7 | 8.481 | 17.019 | F# |
| 8 | 9.436 | 16.064 | G |
| 9 | 10.338 | 15.162 | G# |
| 10 | 11.189 | 14.311 | A |
| 11 | 11.992 | 13.508 | A# |
| 12 | 12.750 | 12.750 | B (Octave) |
| 13 | 13.466 | 12.034 | C |
| 14 | 14.141 | 11.359 | C# |
| 15 | 14.779 | 10.721 | D |
| 16 | 15.380 | 10.120 | D# |
| 17 | 15.948 | 9.552 | E |
| 18 | 16.484 | 9.016 | F |
| 19 | 16.990 | 8.510 | F# |
| 20 | 17.468 | 8.032 | G |
| 21 | 17.919 | 7.581 | G# |
| 22 | 18.344 | 7.156 | A |
| 23 | 18.746 | 6.754 | A# |
| 24 | 19.125 | 6.375 | B |
Note: The 12th fret is highlighted as it represents one octave (double frequency).
Fret positions are calculated using the equal temperament tuning system.
Key Measurements Summary
Standard Scale Lengths
Guitar Building Tips
Measure scale length from nut to bridge center
The 12th fret should be exactly half the scale length
Use precise measurements for proper intonation
Consider fret wire height when marking positions
Double-check measurements before cutting fret slots
Quick Reference
Understanding Fret Positioning
What are Frets?
Frets are thin metal strips placed across the fingerboard of stringed instruments like guitars, ukuleles, and banjos. They divide the neck into precise segments that produce specific musical notes when the strings are pressed behind them.
Why Precise Spacing Matters
- •Ensures proper intonation across all frets
- •Maintains equal temperament tuning system
- •Creates consistent pitch intervals between notes
- •Allows proper chord formation and melody playing
Mathematical Foundation
Distance from nut = L₀ × (1 - (0.9438743)ⁿ)
Distance from bridge = L₀ ÷ (1.0594631)ⁿ
- L₀: Scale length (nut to bridge distance)
- n: Fret number (1, 2, 3, etc.)
- 1.0594631: 12th root of 2 (semitone ratio)
- 0.9438743: 1 ÷ 1.0594631
Key Fact: The 12th fret is always located at exactly half the scale length, representing one octave higher in pitch.
Equal Temperament System
Chromatic Scale
The Western music system divides an octave into 12 equal semitones: C, C#, D, D#, E, F, F#, G, G#, A, A#, B. Each fret represents one semitone.
Frequency Ratios
Each fret increases the pitch by a factor of 1.0594631 (12th root of 2). After 12 frets, the frequency doubles, creating an octave.