Plumbing Calculators
Free plumbing calculators for contractors and engineers. Calculate pipe sizing, water flow rates, pressure drops, and project costs with instant results.
Why Use Our Plumbing Calculators?
Precise Calculations
Industry-standard engineering formulas ensure accurate results for professional plumbing projects.
Instant Results
Real-time calculations with immediate feedback and comprehensive result analysis.
Mobile Ready
Responsive design works perfectly on phones, tablets, and desktop computers.
Always Free
Professional-grade tools available at no cost for plumbers, engineers, and contractors.
Engineering Standards & Formulas
Flow Calculations
Continuity Equation: Q = A × V
Hazen-Williams: C-factor based flow
Manning's Formula: Open channel flow
Pressure Analysis
Darcy-Weisbach: hf = f(L/D)(V²/2g)
Bernoulli's Equation: Energy conservation
Minor Losses: K-factor calculations
Code Compliance
IPC Standards: International Plumbing Code
ASME Guidelines: Engineering standards
Local Codes: Municipal requirements
Frequently Asked Questions
How do I use the pipe sizing calculator?
Enter your required flow rate (GPM), pipe length, and select your pipe material. The calculator instantly shows the recommended pipe diameter, velocity, and pressure drop to help you choose the right size for your project.
What pipe materials are supported in your calculators?
Our calculators support copper, PEX, PVC, steel, and other common plumbing materials. Each material has different friction factors that are automatically applied to give you accurate results for your specific pipe type.
Do these calculators work offline?
Yes! Once you've loaded the page, all calculators work completely offline. Perfect for job sites with poor internet connection. Add our site to your phone's home screen for instant access anywhere.
Are the calculation results accurate for code compliance?
Our calculators use standard engineering formulas (Hazen-Williams, Manning's, etc.) that meet IPC and ASME standards. However, always verify with local codes and inspectors as requirements can vary by jurisdiction.
Can I save or print my calculation results?
Yes, you can print results directly from your browser or take screenshots. The results include all input parameters and calculated values, making them perfect for job documentation and permit applications.
Do you have calculators for gas line sizing?
Yes! Our gas line sizing calculator handles both natural gas and propane calculations. Enter your BTU requirements and pipe length to get proper gas line sizing that meets safety standards and pressure requirements.