Mountain dulcimer fret calculator
A mountain dulcimer has diatonic frets: the open melody string plays a mixolydian scale, so frets sit only on the notes of that scale: 2, 4, 5, 7, 9, 10 and 12 semitones above the open string, repeating every octave. This calculator starts at a 28½″ (724 mm) scale, as on a McSpadden, and lists every fret from the nut in inches or millimeters.
Mountain dulcimer fret positions, 28½″ (724 mm) scale
Diatonic frets with the 6½ and 13½, measured from the nut. Rows are numbered in order, so row 7 is the 6½ fret and row 8 the 7th (octave).
| Fret | Cents | From nut (mm) | From previous (mm) | To saddle (mm) |
|---|---|---|---|---|
| 1 | 200.0 | 78.99 | 78.99 | 645.01 |
| 2 | 400.0 | 149.36 | 70.37 | 574.64 |
| 3 | 500.0 | 181.61 | 32.25 | 542.39 |
| 4 | 700.0 | 240.79 | 59.18 | 483.21 |
| 5 | 900.0 | 293.51 | 52.72 | 430.49 |
| 6 | 1000.0 | 317.67 | 24.16 | 406.33 |
| 7 | 1100.0 | 340.47 | 22.81 | 383.53 |
| 8 | 1200.0 | 362.00 | 21.53 | 362.00 |
| 9 | 1400.0 | 401.49 | 39.49 | 322.51 |
| 10 | 1600.0 | 436.68 | 35.19 | 287.32 |
| 11 | 1700.0 | 452.81 | 16.13 | 271.19 |
| 12 | 1900.0 | 482.39 | 29.59 | 241.61 |
| 13 | 2100.0 | 508.75 | 26.36 | 215.25 |
| 14 | 2200.0 | 520.83 | 12.08 | 203.17 |
| 15 | 2300.0 | 532.24 | 11.40 | 191.76 |
| 16 | 2400.0 | 543.00 | 10.76 | 181.00 |
| 17 | 2600.0 | 562.75 | 19.75 | 161.25 |
| 18 | 2800.0 | 580.34 | 17.59 | 143.66 |
| 19 | 2900.0 | 588.40 | 8.06 | 135.60 |
| 20 | 3100.0 | 603.20 | 14.79 | 120.80 |
| 21 | 3300.0 | 616.38 | 13.18 | 107.62 |
| 22 | 3400.0 | 622.42 | 6.04 | 101.58 |
| 23 | 3600.0 | 633.50 | 11.08 | 90.50 |
How to use it
- Type your scale length, nut to bridge, before compensation. Switch between inches and mm beside the field.
- Pick the Fret system: diatonic with the 6½ and 13½ frets (the usual layout today), purely diatonic, or every half fret (1½, 4½, 6½, 8½, 11½, 13½).
- Set the number of frets. Half frets count as frets, so the table numbers them in order: with the 6½ included, row 7 is the 6½ and row 8 is your 7th fret.
- Tap Print template, keep the scale at 100% and measure the 100 mm bar before you mark the fretboard.
Help and explanations
On that scale the 1st fret is 3.110″ (78.99 mm) from the nut, the 6½ fret 13.405″ (340.47 mm) and the 7th fret, the octave, lands at half the scale: 14.252″ (362.00 mm). The template prints at full size on Letter or A4, with a 100 mm bar to check the printout before you saw a slot.
How dulcimer frets are placed
The positions come from the same equal-tempered formula as a guitar, d = L − L ÷ 2^(s/12), but only the semitone steps of the diatonic scale get a fret. Wikipedia's Appalachian dulcimer article and Bear Meadow's mode chart describe the pattern: open string mixolydian, the 3rd fret starting the ionian (major) scale. The 6½ fret is a half step below the octave (semitone 11) and the 13½ is an octave above it (semitone 23); Folkcraft's fret position reference also lists the 1½, 8½ and 13½ extras.
Because the count includes half frets, the dulcimer's fret numbers and the table's row numbers part ways after the 6th fret. The distances don't depend on wood, string gauge or the number of strings.
Common dulcimer scale lengths
Most mountain dulcimers fall between 24″ and 29″ (610 to 737 mm). McSpadden's standard is 28½″, and many makers build around 26″ to 27″. On a 26½″ scale (673.1 mm) the 1st fret sits at 2.891″ and the 7th at 13.250″; on a 25″ scale they move to 2.728″ and 12.500″.
To find the scale of an existing dulcimer, measure from the nut to the 7th fret (the octave) and double it. The bridge is set slightly back for compensation, so don't measure to it.
Tips
- Mark every fret from the nut, never by adding up the gaps between frets.
- Check the gauges for your scale in the dulcimer string tension calculator.
- Strung and tuned? Compare the 7th fret with the open string using the intonation checker and nudge the bridge until they agree.
Frequently asked questions
What is the fret spacing on a mountain dulcimer?
On a 28½″ (724 mm) scale, from the nut: 1st fret 3.110″, 2nd 5.880″, 3rd 7.150″, 4th 9.480″, 5th 11.555″, 6th 12.507″, 6½ 13.405″ and 7th 14.252″, half the scale.
What is the 6½ fret on a dulcimer for?
It adds the note a half step below the octave, so you can play the major scale and keys that need a flat 7th and a natural 7th. On a 28½″ scale it sits 13.405″ (340.47 mm) from the nut, 0.85″ before the 7th fret.
Where is the octave fret on a dulcimer?
The 7th fret is the octave and sits at exactly half the scale length: 14.25″ on a 28½″ dulcimer, 13.25″ on a 26½″ and 12.5″ on a 25″.
What scale length is a mountain dulcimer?
Usually 24″ to 29″ (610 to 737 mm); 26″ to 28½″ is the most common range. Measure the nut to the 7th fret and double it to know yours.
How many frets does a dulcimer have?
It varies by maker, so count the frets on yours. With the 6½ and 13½ included, this calculator lists up to 23, reaching three octaves above the open string (fret 21, 36 semitones) at 24.941″ from the nut on a 28½″ scale.