String Action Gauge

  • 158 Reviews
  • Write a review

Fast, accurate measurements for setups. Our String Action Gauge is a "Swiss Army Ruler" for setup adjustments on any stringed instrument.

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Item # 0670
In stock, ready to ship!




Item # 0670-M
In stock, ready to ship!


Total: $0.00
Quantity: 20


String Action Gauge

Dan Erlewine uses this gauge for checking string height, measuring saddle and pickup heights and more.

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Fast, accurate measurements for setups. Our String Action Gauge is a "Swiss Army Ruler" for setup adjustments on any stringed instrument.

This pocket-size stainless steel rule has become a luthier's favorite in busy shops. It's the best way yet to get vital measurements on acoustic and electric instruments.
• String height
• Bridge saddle height
• Saddle slot depth
• Fret slot depth (unbound fingerboards)
• Nut height
• Pickup polepiece height

No more "three-and-a-half-64ths or 3/32" plus one of those little lines." This gauge measures in ways that regular rulers can't. —Dan Erlewine

Developed here at Stewart-MacDonald by Dan Erlewine and Don MacRostie, the gauge features a progressive string height scale: simply slide it across the frets and read the measurement under the string. It's faster to use than any ruler, and stays parallel to the fingerboard—much easier than trying to hold a ruler perpendicular to a rounded fret. The string height markers are graduated from .010" to .140" on the inch model, and from 0.25mm to 3.50mm on the metric version.

The back of the gauge has a time-saving fractional/decimal/metric conversion chart.

The String Action Gauge is made of durable stainless steel with precision-etched markings, and fits right in your pocket.

Tip: You can use the gauge to set router depth, instead of a shop ruler. It sits solidly on your router base, with the scale right where you need it.

Product Instructions

Making a Nut, Step-by-Step

Dan Erlewine, of Stewart-MacDonald's R&D Team, walks you through making and installing a new nut.

Product Instructions

String Action Gauge

How to determine string action with the String Action Gauge.

Product Instructions

Metric String Action Gauge

How to determine string action with the Metric String Action Gauge.

Ratings & Reviews

String Action Gauge

  • Based on 158 Reviews
Displaying 12 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Write a review

Great Tool

By Jim M from Walton, KY
(Customer's Reviews) Thursday, June 09, 2011

Makes setting up my guitars very easy!!


By aNovitiate
(Customer's Reviews) Friday, May 27, 2011

a REALLY neat, precise way to measure string height over the frets, that is a LOT easier & faster than measuring the same with a micrometer.

How did I get by without it?

By Muso.Greg from Australia
(Customer's Reviews) Thursday, May 26, 2011

This is a great tool. I had to get one for the work bench and one to carry with me as there are so many uses for it!


By FT 150BL from france
(Customer's Reviews) Tuesday, May 24, 2011

Excellent outil, trFs facile d'utilisation. Et pas cher. Bravo !


(Customer's Reviews) Sunday, May 15, 2011

Small and big at the same time, wow.

good tool

By webster designs from VA
(Customer's Reviews) Friday, May 13, 2011

just got this a few weeks ago and i have used it many times already. it is a really good way to see the string height. highly recommend.

Use it ALL the time

By Scott B from Vestal, NY,  USA
(Customer's Reviews) Thursday, May 12, 2011

I have two of these, one I have in my tool box for guitar repairs (for customers). The other is in my gig bag, just in case I need to do a quick setup for myself or one of my band mates.
I think this is one of the MOST used tools I own (besides a string winder).

Perfection Attained!

By Rustyg61 from Pasadena, TX
(Customer's Reviews) Tuesday, May 03, 2011

I bought a new Alembic bass in February & fought it for 6 weeks trying to get the action low with no buzz, then I bought the String Action Gauge from StewMac & within 10 minutes I had the action perfect! I had been measuring wrong with a ruler for 6 weeks! I was ready to drive to Dallas to have my bass set up by a pro, but now I don't need to! This tool is a must for anyone who works on their own guitar or bass!

Excellent Tool

By RDSTONE from Cibolo,TX
(Customer's Reviews) Tuesday, May 03, 2011

For years I spent time trying to get the proper distance from the strings to the frets. I never was able to do it without having my eyes roll back in my head while I stared for hours. With this tool I was done in less than 10 minutes without eye strain or pushing or holding frets. I should have bought one of these years ago.

I'm impressed!!!

By M. Fermont from The Netherlands
(Customer's Reviews) Wednesday, April 27, 2011

Wow, it has a lot of options.
Very accurate, I thought my Taylor 412CE sounds OK....I needed some practice but I was surprised about the difference, a lot better!

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Shown on page 16 of our latest catalog.