Printable string height ruler
Print it, check it against a bank card, and measure your string height at home. Free.
How to use it
- Print at 100 percent. Turn off “fit to page”.
- Lay a bank card on the black bar. The ends should line up.
- Cut out the ruler. Cut the left end where the black band ends, because that edge is zero.
- Stand it on the fret your maker measures at: the 17th for Fender electrics and basses, the 12th for most acoustics. Read to the underside of the string without pushing it up.
A paper ruler is less exact than a steel gauge. Its finest marks are half a millimetre and 1/64 inch.
What to aim for
Each sheet prints the heights for its kind of guitar. They are starting points: set what plays well for you.
| Fingerboard radius | Low E (bass side) | High E (treble side) |
|---|---|---|
| 7.25" | 5/64" (2.0 mm) | 4/64" (1.6 mm) |
| 9.5" to 12" | 4/64" (1.6 mm) | 4/64" (1.6 mm) |
| 15" to 17" | 4/64" (1.6 mm) | 3/64" (1.2 mm) |
From Fender’s Stratocaster and Telecaster setup procedures. Other makers: use their own figures and fret.
| At the 12th fret | Low E (bass side) | High E (treble side) |
|---|---|---|
| Starting range | 2.4 to 2.8 mm (6/64" to 7/64") | 1.6 to 2.0 mm (4/64" to 5/64") |
Our starting range for testing, not a maker’s factory figure: Martin and Taylor publish no 12th-fret height. Not for nylon-string or 12-string guitars.
| Fingerboard radius | E (bass side) | G (treble side) |
|---|---|---|
| 9.5" to 12" | 6/64" (2.4 mm) | 5/64" (2.0 mm) |
From Fender’s bass setup procedure, the 9.5" to 12" radius row. Other radii and makers: use their own figures.
For your model’s own numbers, use the factory specs lookup. The guitar action height chart, in mm and inches explains how to measure and convert.
All six sheets
Questions
- How do I know the ruler printed at the right size?
- The black bar at the top of the sheet is 85.6 mm long, the width of a bank card. Lay a card on it: if the ends line up, the ruler is true to size. If not, print again at 100 percent with "fit to page" turned off.
- Which fret do I measure string height at?
- Use the fret your guitar’s maker uses. Fender measures its electric guitars and basses at the 17th fret. Acoustic heights are usually given at the 12th fret.
- Is a paper ruler accurate enough?
- It is close enough to tell whether a string is high or low. Its finest marks are half a millimetre and 1/64 inch, so a steel action gauge or feeler gauges are better for the last fine adjustment.
- Why mm on one edge and 64ths on the other?
- Makers publish string heights in both. Fender gives fractions such as 4/64 inch, and many other makers give millimetres, so you can read the number in the same units as your spec.
More setup tools
- Action height calculator: a target height for your guitar and playing style.
- Fret buzz finder: the likely cause of a buzz and the first fix to try.
- Factory specs lookup: the factory action, relief and pickup heights for your model.
Sources
- Fender: How do I set up my Stratocaster guitar properly?, checked September 2026
- Fender: How do I set up my Telecaster guitar properly?, checked September 2026
- Fender: How do I set up my bass guitar properly?, checked September 2026
The acoustic range is our own starting point, not a maker’s figure. The bank card size is the ISO/IEC 7810 ID-1 standard.