Copper Tubing Size Chart
Understanding the proper sizing of copper tubing can play a critical role in ensuring the efficiency, reliability, and safety of both plumbing and HVAC systems. As a small business owner, operator, or contractor, knowing the correct tube/pipe diameter in every situation can help with everything from maintaining optimal flow rates to preventing leaks and other issues down the road.
Use the chart provided below when selecting copper pipe and tubing for your project to ensure safe, efficient results and long-lasting performance.
Copper Pipe and Tubing Size Chart
To correctly and easily interpret our copper pipe and tubing size chart, make sure you understand the key differences between each of following measurements first.
- Nominal Pipe Size (NPS): Copper pipes are measured by their nominal size, not the actual diameter. This means that the nominal size is a reference, but the actual outside diameter (O.D.) will be slightly larger.
- Outside Diameter (O.D.): The actual outside diameter of the pipe will usually be bigger than the nominal size. For example, a copper pipe with a nominal size of ½" will actually have an outside diameter of approximately 0.625".
- Wall Thickness: Copper pipes come in various wall thicknesses, categorized as K, L, and M. These designations indicate the thickness and pressure ratings, so it’s important to match the type to your application.
| Copper Pipe & Tubing I.D. and Thickness Chart | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Nominal Pipe Size | Outside Diameter (O.D.) | Inside Diameter (I.D.) | Wall Thickness | ||||||
| Type | |||||||||
| K* | L** | M*** | DWV**** | K | L | M | DWV | ||
| 1/4" | 0.375 | 0.305 | 0.315 | — | — | 0.035 | 0.03 | — | — |
| 3/8" | 0.5 | 0.402 | 0.43 | 0.45 | — | 0.049 | 0.035 | 0.025 | — |
| 1/2" | 0.625 | 0.527 | 0.545 | 0.569 | — | 0.049 | 0.04 | 0.028 | — |
| 5/8" | 0.75 | 0.652 | 0.666 | — | — | 0.049 | 0.042 | — | — |
| 3/4" | 0.875 | 0.745 | 0.785 | 0.811 | — | 0.065 | 0.045 | 0.032 | — |
| 1" | 1.125 | 0.995 | 1.025 | 1.055 | — | 0.065 | 0.05 | 0.035 | — |
| 1-1/4" | 1.375 | 1.245 | 1.265 | 1.291 | 1.295 | 0.065 | 0.055 | 0.042 | 0.04 |
| 1-1/2" | 1.625 | 1.481 | 1.505 | 1.527 | 1.541 | 0.072 | 0.06 | 0.049 | 0.042 |
| 2" | 2.125 | 1.959 | 1.985 | 2.009 | 2.041 | 0.083 | 0.07 | 0.058 | 0.042 |
| 2-1/2" | 2.625 | 2.435 | 2.465 | 2.495 | — | 0.095 | 0.08 | 0.065 | — |
| 3" | 3.125 | 2.907 | 2.945 | 2.981 | 3.03 | 0.109 | 0.09 | 0.072 | 0.045 |
| 3-1/2" | 3.625 | 3.385 | 3.425 | 3.459 | — | 0.12 | 0.1 | 0.083 | — |
| 4" | 4.125 | 3.857 | 3.897 | 3.935 | 4.009 | 0.134 | 0.114 | 0.095 | 0.058 |
| 5" | 5.125 | 4.805 | 4.875 | 4.907 | 4.981 | 0.16 | 0.125 | 0.109 | 0.072 |
| 6" | 6.125 | 5.741 | 5.845 | 5.881 | 5.959 | 0.192 | 0.14 | 0.122 | 0.083 |
| 8" | 8.125 | 7.583 | 7.725 | 7.785 | — | 0.271 | 0.2 | 0.17 | — |
| * K—thick walled; underground residential, commercial, and industrial uses. |
|---|
| ** L—medium walled; residential and commercial uses |
| *** M—thin walled; above-ground residential and light commercial uses. |
| **** DWV—Drain/Waste/Vent; non-pressurized |
Find Copper Tubing for Every Job
Selecting the right copper tubing or pipe size is essential for maintaining efficiency, preventing leaks, and ensuring the safety of both plumbing and HVAC systems. By choosing the correct diameter for your clients' and customers' projects, you can ensure your project’s long-term performance and efficiency, leading to a successful installation every time.
Shopping for copper pipes or tubing, copper fittings, and related items for your business? Find everything you need to get the job done at Zoro.com!
Product Compliance and Suitability
The statements contained in this guide are intended for general informational purposes only. Such statements do not constitute a product recommendation or representation as to the appropriateness, accuracy, completeness, correctness, or currentness of the information provided. Information provided in this guide does not replace the use by you of any manufacturer instructions, technical product manual, or other professional resource or adviser available to you. Always read, understand, and follow all manufacturer instructions.
