Fret Positions Calculator

The scale length of a guitar is the distance between the nut and the saddle. Most guitars have a scale length around 25" (635 mm), with baritone guitars going up to 30" (762 mm).

The 12th fret is located halfway between the nut and the saddle and represents an octave, which is a doubling or halving of a frequency.

In the equal temperament system, an octave is divided into 12 semitones, which are the smallest increment of pitch on a guitar (ignoring bends).

To calculate the position of each fret, we can use the "12th root of 2" formula. It calculates the ratio between the length of the string between the nut and a given fret, and the length of the entire string (scale length). We find the position of a fret $n$ by multiplying the distance between the nut and saddle by this ratio:

Where

• $L_n$ = distance from the nut to the fret
• $L_0$ = scale length
• $n$ = number of the fret

For example, for the 4th fret on a 635mm (25") instrument, the formula would be

The calculator above applies this formula to all frets so you don't have to do it manually.