JR's Duct Calculator

My ductulator because sometimes it's quicker to build your own tool than find a decent one online. This calculator was created out of necessity and boredom and shared because good tools should be accessible and free. Note: Double-check all calculations and verify against local codes. Use at your own discretion. Feel free to share - no ads, no tracking, just a tool. Email - jesse@obandco.com.au if you have any suggestions for additional features

📊 Duct Sizing Parameters
Global Sizing Constraints
Single Calc
Velocity Size
Pressure Size
Combined Size
Velocity Constraints
Size Constraints (Rectangular)
Pressure Drop Constraints
Size Constraints (Rectangular)
Sizing Method
Most Restrictive: Satisfies both constraints (may result in a larger duct).
Most Efficient: Satisfies at least one constraint (may result in a smaller duct).
Velocity & Pressure Constraints
Size Constraints (Rectangular)
📈 Results & Analysis
Enable color coding based on industry standards
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Enter parameters and calculate to see detailed results

📜 Calculation History

Your calculation history will appear here.