Skip to Content

Sheet Metal Gauge Chart: Accurately Find Gauges for All Metal types

Sheet Metal Gauge Chart:  Accurately Find Gauges for All Metal types

If you’re looking to find basic measurements such as the thickness of sheet metal, you’ll want to know how to use and read sheet metal gauge charts.

This is a handy skill since sheet metal is one of the fundamental building materials used in construction and metalworking.

You’ll come across many everyday objects that use it such as your coffee maker and your car.

Sheet metals are industrially formed into thin, flat sheets and can be molded and bent into various shapes and forms based on how you intend to use them.

They can be made from different metals like tin, steel, copper, brass, and other materials.

cutting large sheet metal piece

When working with sheet metal, you’ll inevitably come across the gauge rating which refers to the measured thickness of sheet metal.

A sheet metal gauge size chart will help you translate this measurement.

Whether you’re a builder looking to freshen up your knowledge on the subject or a do-it-yourself enthusiast with a home project, this article on sheet metal gauge thickness will show you how to read and use sheet metal gauge charts.

Ready? Let’s get to it!

Overview of Sheet Metal Gauge Charts and How to Read Them

Gauge charts can be used to measure the thickness of sheet metal regardless of the material it’s made from.

They’re precise and indicate the standard and metric units of measurement.

It may be easier for you to understand how they work if we described them as sheet metal gauge conversion charts.

sheets of metal

A gauge chart will show you the exact thickness of a sheet metal.

If, for example, an artist was looking for a #20 copper sheet metal for a sculpture, it doesn’t mean that he or she is looking for a sheet that’s 20 inches or 20 millimeters thick.

You’ll need to check a gauge chart to see the corresponding thickness a #20 refers to.

In this case, the equivalent sheet metal thickness is 0.035 inches or 0.88 millimeters.

Remember that when it comes to sheet metal, the number 20 doesn’t directly tell you how thick the sheet is.

You have to use a gauge chart to find out the indicated thickness in inches and millimeters.

24 gauge stainless steel sheet example

A second thing to keep in mind is that every material that sheet metal comes in has a different metal gauge chart that you ought to use.

Using our same example from above, a #20 sheet metal in aluminum won’t have the same thickness if it were made from copper.

Again, the thickness will differ if your sheet is made of brass and other materials.

It’s thus necessary to know the material of a specific sheet metal before referring to your gauge chart.

The Gauge Chart in Detail

While the number that refers to the thickness of sheet metal doesn’t directly translate into a unit of measurement, a general rule to keep in mind is that the higher the number, the thinner a sheet metal is.

This is true for reading all sheet metal gauges regardless of what the sheet metal is made of.

You might be wondering why we use gauges, a not so straightforward method for measuring thickness.

Well, we have the British iron wire industry from the 1800s to thank for that.

To this day, the sheet metal gauge to decimal chart is still widely used across industries.

While it can seem pretty intimidating at first, reading sheet metal gauges is easy as long as you know the gauge (or thickness) of the sheet metal and the material you need.

To make it even simpler, we summarized the two principles to remember below:

First Principle

Whether moving up or down, the gauge of a steel sheet doesn’t directly translate into its decimal equivalent.

Second Principle

Different types of metal have their corresponding charts.

Two steel sheets made from different materials but have the same gauge don’t mean that they have the same thickness.

To ensure that you get steel sheets with the right gauges, identify the type of metal you’ll be working with so that you can refer to the right steel gauge chart.

Let us help you familiarize yourself with the different materials that you can consider using.

TIP:
Check out our full gauge charts below to cross reference all gauge sizes to decimal widths of sheet metal.

Common Metals Used In Sheet Metal Manufacturing and Fabrication

manufacturing sheet metal gauges

The manufacturing and fabrication of sheet metals take a number of factors into account, including electrical conductivity, metal strength, malleability, and corrosion resistance.

Depending on these factors, each sheet metal will have different uses.

Common applications are construction and technology manufacturing.

Here are common metals used in sheet metal manufacturing and fabrication:

Carbon Steel

carbon steel sheet metal plates

While all steel has a carbon component, carbon steel has a more concentrated amount of it.

Although sheet metal is generally malleable, carbon steel is stronger and less malleable than other types of metal.

There are three primary classifications of carbon steel: low or mild carbon, medium, and high carbon steel.

Carbon steel with lower carbon content is often used in railings for staircases, gates, and fences.

Medium carbon steel is often used in cars and most kitchen appliances while steel with the highest carbon content is typically found in steel wires.

Aluminum

aluminum sheet metal ex

Aluminum steel is pricier and more lightweight than standard steel. It also makes an excellent alternative for regular steel.

Not only is it more malleable, but it offers excellent electric conduction and has thermal properties.

In addition, aluminum (like stainless steel) isn’t prone to rust.

Although it has many benefits, aluminum also has its downsides.

It is weaker than standard steel and isn’t recommended for surfaces whose temperatures exceed 400 degrees Fahrenheit.

Aluminum is often used in AC units and refrigerators, but it is also used in various aerospace applications.

Stainless Steel

stainless steel sheet metal

Stainless steel is pricier than ordinary steel because of the chromium component that protects it against rust.

Stainless steel also has a shiny and silver exterior that makes it aesthetically pleasing.

You’ll often see it used in kitchen appliances, medical supplies and instruments, and other stainless steel products.

Though stainless steel is pretty malleable, using it with other materials that have different properties can affect it and make it susceptible to corrosion.

Galvanized Steel

galvanized steel sheet metal

Steel coated in zinc makes it resistant to corrosion and protects it against the damaging effects of air and water.

The resulting steel type is called galvanized steel.

Because of its resistance to the elements, this type of steel is often used in recesses that can’t be covered with paint and other protective coatings.

Another advantage to galvanized steel is its longer shelf life.

It can last for up to 20 years in extreme weather conditions and up to 50 years in more normal environments.

Galvanized steel is also cheaper than its other counterparts and requires less preparation before you can use it.

Brass

thick gauge brass sheet metal

Copper and zinc are the main components for brass.

This one is well known for its excellent acoustic properties which is why brass is the metal of choice in various musical instruments.

Although it’s more often utilized for its acoustic properties, brass is also found in everyday items like nuts, bolts, doorknobs, and pipes.

Copper

copper sheet metal example

Though copper can be expensive, it isn’t as strong as steel and aluminum.

However, many like using copper because it’s easy to work with whether you’re machining or welding.

Also, the fact that it’s easier to bend and offers great aesthetics makes it the steel of choice for artists. 

Another benefit of using copper is it doesn’t rot. In fact, it ages well and can provide a unique patina finish when left to the elements, making it ideal for pots and pans.

Copper is also commonly used in electronic equipment because of its ability to conduct electricity.

Examples of Using the Chart

Let’s assume that person A needs a 14 gauge copper sheet. Taking the first principle into account, a 14 gauge copper sheet and its corresponding gauge chart means that:

  • The decimal value of a 14-gauge copper sheet metal is equivalent to 2.108 millimeters or 0.0830 inches
  • Moving lower to a 12-gauge copper sheet metal is equal to 2.764 millimeters or 0.109 inches
  • Moving up to a 16-gauge copper sheet metal is equivalent to 1.651 millimeters or 0.065 inches

The whole number “14 gauge” indicates a certain standardized thickness of sheet metal.

cutting thin gauge sheet metal using chart

Based on our second principle, the decimal equivalent of a specific gauge differs from one metal type to another.

If person B wants to use a 14 gauge aluminum metal sheet, then:

  • A 14-gauge aluminum sheet metal is equal to 1.628 millimeters or 0.064 inches
  • However, if person B wants to use a 14 gauge copper sheet metal, its equivalent thickness would be different and would instead be 2.108 millimeters or 0.083 inches

Although the gauge number is the same, the metal type is different and thus the chart used and decimal equivalent of the gauge will also differ.

Sheet Metal Gauge Charts for All Metal Types

Carbon Steel Metal Gauge Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Carbon Steel Gauge Chart

Gauge Number

Inches

Millimeters

7

0.1793

4.554

8

0.1644

4.175

9

0.1495

3.797

10

0.1345

3.416

11

0.1196

3.038

12

0.1046

2.656

14

0.0747

1.897

16

0.0598

1.518

18

0.0478

1.214

20

0.0359

0.911

22

0.0299

0.759

24

0.0239

0.607

 

Aluminum Sheet Metal Gauge Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Aluminum Gauge Chart

Gauge Number

Inches

Millimeters

7

0.1443

3.665

8

0.1285

3.264

9

0.1144

2.906

10

0.1019

2.588

11

0.09074

2.305

12

0.08081

2.053

14

0.06408

1.628

16

0.05082

1.291

18

0.0403

1.024

20

0.03196

0.812

22

0.02535

0.644

24

0.0201

0.511

26

0.01594

0.405

28

0.01264

0.321

30

0.01003

0.255

 

Stainless Steel Metal Gauge Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Stainless Steel Gauge Chart

Gauge Number

Inches

Millimeters

8

0.17187

4.365

9

0.15625

3.968

10

0.14062

3.571

11

0.125

3.175

12

0.10937

2.778

14

0.07812

1.984

16

0.0625

1.587

18

0.05

1.27

20

0.0375

0.9525

22

0.03125

0.7937

24

0.025

0.635

26

0.01875

0.476

28

0.01562

0.396

30

0.0125

0.3175

 

Galvanized Sheet Metal Gauge Thickness Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Galvanized Steel Gauge Chart

Gauge Number

Inches

Millimeters

8

0.1681

4.269

9

0.1532

3.891

10

0.1382

3.51

11

0.1233

3.1318

12

0.1084

2.753

14

0.0785

1.9939

16

0.0635

1.6129

18

0.0516

1.31

20

0.0396

1.005

22

0.0336

0.853

24

0.0276

0.701

26

0.0217

0.551

28

0.0187

0.474

30

0.0157

0.398

 

Brass Sheet Metal Gauge Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Brass Gauge Chart

Gauge Number

Inches

Millimeters

7

0.1443

3.665

8

0.1285

3.264

9

0.1144

2.906

10

0.1019

2.588

11

0.09074

2.305

12

0.08081

2.053

14

0.06408

1.628

16

0.05082

1.291

18

0.0403

1.024

20

0.03196

0.812

22

0.02535

0.644

24

0.0201

0.511

26

0.01594

0.405

28

0.01264

0.321

30

0.01003

0.255

 

Copper Sheet Metal Gauge Chart in Standard (Inches) and Metric (Millimeter) Equivalents

Copper Gauge Chart

Gauge Number

Inches

Millimeters

7

0.18

4.572

8

0.165

4.191

9

0.148

3.759

10

0.134

3.404

11

0.12

3.048

12

0.109

2.764

14

0.083

2.108

16

0.065

1.651

18

0.049

1.245

20

0.035

0.889

22

0.028

0.711

24

0.022

0.559

26

0.018

0.457

28

0.014

0.356

30

0.012

0.305

FAQs

Are sheet metals with a higher gauge number stronger?

No, sheet metals with higher gauge numbers aren’t stronger. It’s actually the other way around, unlike say, a rebar grade size chart which is as you might expect.

The lower the sheet metal gauge number, the thicker the sheet metal will be.

If, for example, you have a 10-gauge copper sheet metal and a 14-gauge sheet metal, expect the 10-gauge copper sheet metal to be stronger because it is thicker.

Here is a video tutorial about gauge numbers: 

How can I tell what gauge my steel metal sheet is?

The first thing you need to do is take a measuring tape and measure the thickness of your sheet metal.

Measure the thickness in millimeters to improve the accuracy of your measurement.

Once you’ve measured it, multiply the thickness by 0.03937 to get the equivalent in inches. Let’s assume you measured a brass sheet that is 2.906 millimeters thick.

Multiply 2.906 by 0.03937 to get the measurement in inches (which should be 0.1144 inches).

Consult a brass sheet metal gauge chart, for example.

Check the inches and the gauge corresponding to your measured decimal value.

Since the product is 0.1144 inches, you have a 9-gauge brass sheet metal.

To skip the step where you multiply the thickness, you can also find the equivalent gauge by using a brass sheet metal gauge chart in mm.

What is the most commonly used sheet metal in construction?

The most commonly used gauge for architectural applications is 18, 20, 22, 24, and 26.

On the other hand, heavier or thicker gauge sheet metal is used for structural components.

thin gauge aluminum metal sheet

What are the best metal gauges and metal types for crafting and sculptures?

Since thinner metals are more malleable, the best sheet metal for crafting are those with higher gauge numbers.

In most cases, the best type of metal for crafting and artistic projects is brass and copper.

Both are easy to bend and cast. They also age without corrosion.

—–

Reading a sheet metal gauge chart is pretty easy as long as you know the gauge number and the type of sheet metal you’ll be using.

Now that your sheet metal gauge crash course is complete, you can get what you need with confidence whether you’re constructing something for your home, working on a renovation project, or getting one for an artistic masterpiece.