Pipe Flow Calculator

Use this pipe flow calculator to estimate velocity, flow rate (GPM), and friction loss.

Related Calculators

Water Pressure Calculator | Pump Calculator | Volume Calculator

How to Use

Enter pipe size, pressure, and length to estimate flow characteristics.

Example

For a 1-inch pipe, 100 ft long, at 40 psi using PVC:

• Velocity ≈ 21.5 ft/s
• Flow Rate ≈ 220 GPM
• Friction Loss ≈ 0.30 psi/100 ft

Tips

• Larger diameter = higher flow, lower friction
• Longer pipes increase friction loss
• Smoother materials reduce resistance

Frequently Asked Questions

Is this exact?
No, this is an estimate. Real systems vary.

What affects flow most?
Diameter and pressure.