Pipe Size Calculator
Calculate required pipe diameter based on flow rate and desired velocity. Includes recommendations for copper, PVC, and steel pipes.
Pipe Size Comparison
| Nominal | Inner Dia | Velocity | Status |
|---|---|---|---|
| 0.5" | 0.545" | 13.8 ft/s | Too Small |
| 0.75" | 0.785" | 6.6 ft/s | Too Small |
| 1" | 1.025" | 3.9 ft/s | OK |
| 1.25" | 1.265" | 2.6 ft/s | OK |
| 1.5" | 1.505" | 1.8 ft/s | OK |
| 2" | 1.985" | 1.0 ft/s | OK |
| 2.5" | 2.465" | 0.7 ft/s | OK |
| 3" | 2.945" | 0.5 ft/s | OK |
Pipe Sizing Formula
Pipe area = Flow Rate / Velocity. Recommended velocity: 4-8 ft/s for water supply, 2-4 ft/s for drainage. Size up to the nearest standard pipe size.
Disclaimer:This tool is provided “as is” for informational and educational purposes only. Results may not be 100% accurate. ToolBird makes no warranties, express or implied, regarding the accuracy, reliability, or completeness of any output generated by this tool. This tool does not constitute professional, legal, financial, medical, or tax advice. Always consult a qualified professional for important decisions. By using this tool, you agree that ToolBird and its operators shall not be held liable for any damages, losses, or consequences arising from the use of this tool or reliance on its results. All processing occurs in your browser — we do not store, transmit, or access your data. Use at your own risk.