Metal sheets come in various gauges and thicknesses. Each thickness is specific in its usability. Manufacturers always refer to the gauges of metal sheets before choosing them for any product. This increases the importance of knowing the newest sheet metal gauge chart.
It helps to know if any specific gauge provides the thickness your product needs. Generally, metal gauge charts are the least understood. This is mainly due to the involvement of many numbers and measurements. Don’t you know how to use a metal gauge chart? Worry not! This article will discuss the gauge chart used in metal sheet selection.
What is Sheet Metal Gauge?
Let’s start with a basic understanding of gauges.
In the sheet metal industry, the term ‘gauge’ is used to specify the thickness or size of sheet metal. Each gauge number indicates a specific thickness of metal. Each material (metal) has its gauge chart. This chart indicates which gauge of any particular thickness.
Generally, thickness is a key parameter when measuring metal sheets, right? However, an international gauge is used instead of thickness. Remember, a gauge is a unit to represent thickness. However, it streamlines the measurement.
For example, you have a gauge of three steel sheets. It will have a thickness of 0.2391 inches or 6.07314mm. This measurement is standard worldwide. If someone says gauge three steel sheet, it will have that specific thickness. Similarly, gauge 4 5 6 will have a particular thickness as well. In simple words, gauges are a standard that refers to thickness.
Each metal has its gauge number, which indicates a specific thickness in inches and millimeters. Moreover, the higher the gauge number, the thinner the metal sheet will be, and vice versa. A 5 gauge steel sheet will be thinner than a three gauge steel sheet. This is true in all metal gauge charts.
History of Sheet Metal Gauge
The word ‘gauge’ linguistically originated from the French word ‘Jauge’. This word means “capacity that a specific container must have.” The name of the gauge suggests that it’s related to the steel, iron, and wire-drawing industries. The gauge has been in use for hundreds of years.
Archaeological evidence indicates that it existed in the ancient past. Traditional thickness measurements use gauges. The British iron wire industry first used this word. At that time, there was no standard thickness measurement available. The wire-drawing process and the properties of iron set the gauge number sizes.
In the 19th century, gauges were measured and described in fractions of an inch. One gauge was legalized and made to be the Standard Wire Gauge in the UK. The convenience of craftspeople was a crucial factor in the gauge’s standardization. With the birth of the International System of Units in the 20th century, the gauge was to be replaced.
Sheet Metal Gauge Charts
The metal gauge chart is a table that indicates the thickness of different metal sheets. This chart comes with different gauge numbers. Each number is associated with a specific thickness in inches and millimeters. So, it helps identify how thick a sheet is without measuring it.
Once you know the gauge number, you know the exact thickness. The metal gauge chart consists of gauge numbers and thickness in both inches and millimeters. Each metal sheet has its gauge chart. For example, you cannot use steel gauge charts for aluminum metal sheets. Each gauge number indicates a specific thickness level (in inches and millimeters).
The gauge numbers and the measured inches and millimeters are independent of different sheet metals. For example, gauge number 9 for standard steel and aluminum is 0.1495 and 0.1144, respectively. I’ll show you different metal (steel, aluminum, and galvanized) gauge charts in the section below. This will help you understand more about these charts.
1- Standard Steel Gauge Chart
| Gauge | Inches | MM | Gauge | Inches | MM |
| 3 | 0.2391 | 6.07314 | 20 | 0.0359 | 0.91186 |
| 4 | 0.2242 | 5.69468 | 21 | 0.0329 | 0.83566 |
| 5 | 0.2092 | 5.31368 | 22 | 0.0299 | 0.75946 |
| 6 | 0.1943 | 4.93522 | 23 | 0.0269 | 0.68326 |
| 7 | 0.1793 | 4.55422 | 24 | 0.0239 | 0.60706 |
| 8 | 0.1644 | 4.17576 | 25 | 0.0209 | 0.53086 |
| 9 | 0.1495 | 3.7973 | 26 | 0.0179 | 0.45466 |
| 10 | 0.1345 | 3.4163 | 27 | 0.0164 | 0.41656 |
| 11 | 0.1196 | 3.03784 | 28 | 0.0149 | 0.37846 |
| 12 | 0.1046 | 2.65684 | 29 | 0.035 | 0.3429 |
| 13 | 0.0897 | 2.27838 | 30 | 0.012 | 0.3048 |
| 14 | 0.0747 | 1.89738 | 31 | 0.0105 | 0.2667 |
| 15 | 0.0673 | 1.70942 | 32 | 0.0097 | 0.24638 |
| 16 | 0.0598 | 1.51892 | 33 | 0.009 | 0.2286 |
| 17 | 0.0538 | 1.36652 | 34 | 0.0082 | 0.20828 |
| 18 | 0.0478 | 1.21412 | 35 | 0.0075 | 0.1905 |
| 19 | 0.0418 | 1.06172 | 36 | 0.0067 | 0.17018 |
Standard steel gauge thickness chart
2- Galvanized Steel Gauge Chart
| Gauge | Inches | MM | Gauge | Inches | MM |
| 3 | – | – | 20 | 0.0396 | 1.00584 |
| 4 | – | – | 21 | 0.0366 | 0.92964 |
| 5 | – | – | 22 | 0.0336 | 0.85344 |
| 6 | – | – | 23 | 0.0306 | 0.77724 |
| 7 | – | – | 24 | 0.0276 | 0.7004 |
| 8 | – | – | 25 | 0.0247 | 0.62738 |
| 9 | 0.1532 | 3.89128 | 26 | 0.0217 | 0.55118 |
| 10 | 0.1382 | 3.51028 | 27 | 0.0202 | 0.51308 |
| 11 | 0.1233 | 3.13182 | 28 | 0.0187 | 0.47498 |
| 12 | 0.1084 | 2.75336 | 29 | 0.0172 | 0.43688 |
| 13 | 0.0934 | 2.37236 | 30 | 0.0157 | 0.39878 |
| 14 | 0.0785 | 1.9939 | 31 | 0.0142 | 0.36068 |
| 15 | 0.071 | 1.8034 | 32 | 0.0134 | 0.34036 |
| 16 | 0.0635 | 1.6129 | 33 | – | – |
| 17 | 0.0575 | 1.4605 | 34 | – | – |
| 18 | 0.0516 | 1.31064 | 35 | – | – |
| 19 | 0.0456 | 1.15824 | 36 | – | – |
Galvanized steel gauge thickness chart
3- Aluminum Steel Gauge Chart
| Gauge | Inches | MM | Gauge | Inches | MM |
| 3 | 0.2294 | 5.82676 | 20 | 0.032 | 0.8128 |
| 4 | 0.2043 | 5.18922 | 21 | 0.0285 | 0.7239 |
| 5 | 0.1819 | 4.62026 | 22 | 0.0253 | 0.64262 |
| 6 | 0.162 | 4.1148 | 23 | 0.0226 | 0.57404 |
| 7 | 0.1443 | 3.66522 | 24 | 0.0201 | 0.51054 |
| 8 | 0.1285 | 3.2639 | 25 | 0.0179 | 0.45466 |
| 9 | 0.1144 | 2.90576 | 26 | 0.0159 | 0.40386 |
| 10 | 0.1019 | 2.58826 | 27 | 0.0142 | 0.36068 |
| 11 | 0.0907 | 2.30378 | 28 | 0.0126 | 0.32004 |
| 12 | 0.0808 | 2.05232 | 29 | 0.0113 | 0.28702 |
| 13 | 0.072 | 1.8288 | 30 | 0.01 | 0.254 |
| 14 | 0.0641 | 1.62814 | 31 | 0.0089 | 0.22606 |
| 15 | 0.0571 | 1.45034 | 32 | 0.008 | 0.2032 |
| 16 | 0.0508 | 1.29032 | 33 | 0.0071 | 0.18034 |
| 17 | 0.0453 | 1.15062 | 34 | 0.0063 | 0.16002 |
| 18 | 0.0403 | 1.02362 | 35 | 0.0056 | 0.14224 |
| 19 | 0.0359 | 0.91186 | 36 | – | – |
Aluminum metal gauge chart
Frequently Asked Questions
What is a sheet metal gauge chart?
The metal gauge chart is a tabular representation of the thickness of metal sheets. This table has a gauge number associated with a specific thickness. The chart indicates gauge number and thickness in inches and millimeters.
Why is the gauge used instead of just saying the thickness?
Gauge is a more standardized and conventional way to indicate the thickness of metal sheets. It is also used worldwide. Thickness, on the other hand, is known in specific regions but not worldwide. Using gauge makes thickness more streamlined and standardized.
Does a higher gauge number mean thicker metal?
No, a higher gauge number does not mean a higher thickness. Instead, if the gauge number is high, the metal sheet is thinner, and vice versa.
Conclusion
The sheet metal gauge chart is very beneficial in many ways. It helps us choose the sheet of the right thickness without any significant hassle. Without it, you would have to measure each sheet for its thickness. Each metal sheet has its own unique chart.
You should refer to the metal gauge chart to determine the gauge number and specific thickness. In this article, I only mentioned three metals and their charts to help you understand the basics of these charts. You can also contact our team if you need help selecting metal sheets.