What is Radius Gauge and How to Use

Published: 7 Jul 2025

Looking for a way to measure curved surfaces accurately? A radius gauge might be just what you need. This article will help you understand what a radius gauge is, how to use it, and why it’s helpful.

What is a Radius Gauge?

A radius gauge helps to find the size of the curved or rounded edges of an object. A radius gauge set is often used with a fillet gauge to measure outer curves. That’s why it is sometimes called a radius and fillet gauge. It is used by many people in the metalworking, carpentry, and engineering fields rely on it for accuracy.

Types of Radius Gauges

There are different types of radius gauges, and each has a special purpose.

Internal Radius Gauge

It Measures the inside curve.

External Radius Gauge

It Checks the outside curve

Some sets come with a variety of blades for quick measurement of a variety of sizes.

How to Use a Radius Gauge Set

Using a radius gauge is easy:

Choose a blade that matches the curve size you want to check.
Place the blade over the curve or corner you’re checking.
Place the blade on the curve to see if it fits well.
If it doesn’t match, test a different size until it fits.

Radius Gauge Uses

Radius gauges are handy in many fields:

Metalworking: For checking tool edges and parts corners

Carpentry: To match curved wood pieces

Engineering & Manufacturing: for quality control

It helps save time and improves accuracy.

Conclusion

Radius gauges are small tools, but they play a big role in making things just right. From checking corners to improving product design, they’re a must-have for precision work. Got one in your toolbox yet?

FAQs

What is the least count of a radius gauge?

Radius gauges usually don’t have the least count like other measuring tools. They come in fixed sizes, like 1mm, 2mm, etc., for quick checking.

What is the price of a radius gauge?

The price can vary. Basic sets start around $10–$20, while premium ones can vary based on quality and the number of blades.

What is the range of a radius gauge?

The majority of sets cover a range of 1mm to 25mm or more.