Ductulator vs Duct Sizer Calc HVAC

Professional HVAC duct sizing and psychrometric calculations in one powerful app. DuctCalc replaces your physical ductulator with a modern, accurate digital tool trusted by engineers, contractors, and HVAC professionals. DUCT SIZING CALCULATOR Size round, rectangular, and flexible ductwork with ASHRAE-compliant calculations: • Forward Mode: Enter CFM airflow → Get multiple duct size options with velocity, friction loss, and pressure drop for each • Reverse Mode: Select a duct size → See CFM capacity at minimum, ideal, and maximum velocities Supports 6 duct materials: - Galvanized Steel - Flex Duct (extended & compressed) - Duct Board - Fiberglass Lined - PVC/Plastic FITTINGS & PRESSURE DROP Calculate total equivalent length and pressure loss with 10+ standard fittings: - 90° and 45° Elbows (smooth, 3-piece, mitered) - Tees (branch and straight-through) - Reducers and Transitions - Takeoffs (90° and 45°) - Register Boots PSYCHROMETRIC CALCULATOR Complete humid air property analysis with interactive chart: • 4 Input Modes: Dry bulb + wet bulb, relative humidity, dew point, or humidity ratio • Calculates: Enthalpy, specific volume, vapor pressure, saturation pressure, degree of saturation • Altitude correction for non-standard atmospheric pressure • Visual psychrometric chart showing current state point APPLICATION TYPES Pre-configured velocity limits per ASHRAE/ACCA guidelines: - Residential Supply (400-1000 FPM) - Residential Return (300-800 FPM) - Commercial Low Velocity (600-1500 FPM) - Commercial High Velocity (1000-2500 FPM) PROFESSIONAL FEATURES Imperial (I-P) and Metric (SI) units Airflow in CFM, m³/h, or L/s Color-coded status indicators Real-time validation warnings Built-in reference documentation Standard duct size tables (ASHRAE/SMACNA) WHY DUCTCALC? Unlike other apps that only size ducts OR calculate psychrometrics, DuctCalc combines both essential HVAC tools. No more switching between apps. Professional-grade accuracy in your pocket. Perfect for: • HVAC Engineers • Mechanical Contractors • MEP Design Firms • HVAC Technicians • Building Inspectors • Engineering Students Download DuctCalc and replace your old ductulator with the modern HVAC calculator trusted by professionals. Privacy Policy: https://docs.google.com/document/d/1r9oCuYYtQZlKWhZTlrP8Ck73V6NoR8lx82027oWszsA/edit?usp=sharing Terms of Service: https://docs.google.com/document/d/1MAY_7_uIVMnf4QYSpeaaSaSV7cm3-TJApqYVLfTHQ7w/edit?usp=sharing

HVAC Duct Sizing Calculator is the professional duct sizing tool for HVAC technicians, engineers, and contractors. Calculate correct ductwork dimensions based on airflow (CFM), velocity, or friction rate using ASHRAE standard sizes and ACCA Manual D methodology - the industry standard for professional air conditioning system design. SIZING METHODS: CFM-Based Method - Enter airflow and get recommended standard duct sizes instantly Velocity-Based Method - Size ducts by target air velocity (FPM) for proper sizing Friction Rate Method - Default 0.08 in. w.g. per 100 ft or custom pressure drop values DUCT TYPE SUPPORT: Round Duct Sizing - Calculate diameter based on CFM and friction loss Rectangular Equivalent - Find standard rectangular dimensions for any round size Flex Duct Correction - Automatic 10% correction factor for flexible ductwork All Standard Sizes - Results snap to ASHRAE industry-standard dimensions ADVANCED CALCULATIONS: Velocity Check - Ensures airflow stays within safe limits (optimal 400-900 FPM) Pressure Drop Analysis - Darcy-Weisbach calculation per 100 ft of duct Reynolds Number - Full hydraulic analysis for precision engineering Friction Loss Display - See calculated friction for every result OPTIONAL PRO UPGRADE — $2.99 ONE-TIME IN-APP PURCHASE The following features require a separate one-time in-app purchase. They are not required to use the calculator: • Unlimited saved calculation history • PDF export of results • Dark theme • Ad-free experience WHY HVAC PROS USE THIS CALCULATOR: Faster ductwork design than manual slide rules and ACCA charts ASHRAE-compliant and Manual D-verified sizing ensures proper system performance Cross-check velocity and friction rate for perfectly balanced systems Prevents over/undersized ducts that reduce efficiency and increase noise Field calculations without internet connection needed on job sites PERFECT FOR: HVAC design engineers planning new installations HVAC technicians calculating duct replacement sizing HVAC field technicians verifying existing ductwork AC contractors preparing accurate job estimates HVAC students learning Manual D design methodology Residential and commercial HVAC system design Based on ACCA Manual D constant friction method and ASHRAE Handbook fundamentals. Part of HVACTools Suite - the complete HVAC technician app for field calculations, refrigeration tools, and air conditioning diagnostics.