About the Pipe Head Loss Calculator
Friction head loss in a pipe run using Hazen-Williams, with fittings expressed as extra length.
Also known as: friction loss calculator, head loss in pipe, pressure loss pipe, hazen williams loss.
How to use this calculator
- Enter inside diameter, pipe length, flow rate, hazen-williams c and the other fields.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
h_f = 10.67 × L × Q^1.852 ÷ (C^1.852 × d^4.87)
Worked example
Using the values pre-filled in the calculator above:
- Inside diameter = 50 mm
- Pipe length = 100 m
- Flow rate = 200 L/min
- Hazen-Williams C = 140
- Elbows = 4
- Tees = 2
- Valves = 2
the calculator returns:
- Total head loss: 7.149 m
- Pressure drop: 0.7011 bar
- In psi: 10.168
- Equivalent length of fittings: 12.8 m