How far from the saddle or nut should one measure to place the 12th fret?

Question

on a standard-size guitar, the length of the strings between the bridge and nut is 25 1/2 inches. Guitar makers must place the 12th fret at exactly half of the length of the string. How far from the saddle or nut should one measure to place the 12th fret?

Answer 1

If the distance from the inside edge of the nut, to the inside edge of the bridge is exactly 25 1/2 inches, then the 12th fret should be centered on 12 3/4 inches (from either end).

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