Guitar Fret Distance Calculator
Calculates the exact distance from the nut to each fret on a guitar from the scale length, using the equal-temperament rule. Essential for luthiers and DIY builders laying out a new fretboard accurately.
Last updated: September 2026
Formula below · 2 sources (aes.org, Wikipedia) · Updated Sep 2026
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About this calculator
Fret placement follows equal temperament: each semitone divides the octave into 12 equal ratio steps, so each fret is placed at a fraction of the remaining string length. The formula is: fretDistance = scaleLength × (1 − 2^(−fretNumber/12)). The term 2^(−n/12) comes from the twelfth root of two, which defines equal-tempered tuning. Fret slots are always laid out from the nominal scale length with no correction; string stiffness and the stretch from fretting are compensated by moving the bridge saddles back (typically 1–3 mm, more for wound strings), not by moving the frets. For that reason the compensation factor and string gauge inputs do not change the fret positions; they are reminders for setting saddle compensation.
How to use
Suppose you're building a guitar with a 25.5-inch scale length and placing fret 12. Calculation: 25.5 × (1 − 2^(−12/12)) = 25.5 × (1 − 0.5) = 12.75 inches. So the 12th fret sits exactly halfway, 12.75 inches from the nut, confirming the octave relationship. Fret 1 sits at 25.5 × (1 − 2^(−1/12)) ≈ 1.43 inches and fret 5 at about 6.39 inches.
Frequently asked questions
What scale length should I use for a standard electric guitar fret calculator?
Most standard electric guitars use a scale length of 25.5 inches (Fender style) or 24.75 inches (Gibson style). The scale length is measured from the nut to the saddle. Choosing the correct scale length is the single most important input because every fret position is derived from it proportionally. Even a small error in scale length will cause cumulative intonation problems up the neck.
Does string gauge affect fret placement?
No. Heavier strings are stiffer and stretch more when fretted, which makes fretted notes go slightly sharp, but luthiers correct this at the bridge by setting each saddle a little further back (more for heavier and wound strings), not by moving the frets. Fret positions depend only on the scale length, so this calculator ignores the gauge input when placing frets.
What is the compensation factor in a guitar fret position calculator?
Compensation is a deliberate bridge saddle setback that corrects intonation errors caused by fretting action and string elasticity. It is applied at the saddle, never to the fret slots, so the compensation factor input does not change the fret distances this calculator returns. Real instruments typically require saddle compensation of 1–3 mm depending on string type and action height. Luthiers fine-tune this value by measuring intonation at the 12th fret and adjusting the saddle position until the fretted note matches the harmonic.