You don’t have to be the kind of person who loves working on guitars to find a lot of uses for D’Addario’s new String Height Gauge. Sure, luthiers will probably want one in the toolbox, but even players who don’t know a fret file from a nail file might find this tool handy for diagnosing a problem or discovering why one guitar might feel more comfortable to play that another does.

About the same size as a credit card, the String Height Gauge ($14 MSRP; $10 MAP) has both metric and US measurements etched onto a stainless steel plate. String heights are lined up along the long edge of the front and are measured in ten-thousandths of an inch and millimeters. Height measurements are easy to make—just lay the gauge on the top of the 12th fret and measure to the bottom of the string. The markings on the short and long edges can also be used to work out other setup aspects, such as neck relief or string spacing.

The reverse side acts as a ruler, again in both US and metric measurements, and adds a conversion table and recommended string heights for acoustic, electric, and bass guitars. Since the gauge also functions as a highly precise straightedge, you can use it to find any low spots on your frets that may be causing a buzz by laying it across several frets and trying to rock it back and forth.


Even if you’re not a home (or a pro) luthier, the gauge is useful for figuring out why some guitars feel better to you than others, or if something has changed on your guitar, like a low-humidity situation making your guitar more difficult to play. For example, if you find a guitar that plays a lot better than your own, you can use the String Height Gauge to record what it is that feels so good to your fingers and have a professional try to duplicate it on your guitar.

This article originally appeared in the September 2018 issue of Acoustic Guitar magazine.