Electrical Calculator ElecCalc vs Duct Sizer Calc HVAC

Solve electrical calculations faster on site or in the office. ElecCalc gives engineers, electricians, technicians, and students 15 focused tools for wire sizing, voltage drop, breakers, transformers, grounding, motors, power factor, and more. WHY ELECCALC • Electrical calculator toolkit built for field and office work • Wire size, voltage drop, cable ampacity, breaker, transformer, and grounding tools • IEC-based assumptions shown clearly with risk-sensitive results • Calculation history, favorites, and formula reference for repeated work • Clean interface designed for fast checks, not bloated spreadsheets CALCULATORS INCLUDED • Ohm's Law for voltage, current, resistance, and power • Power calculator for active, reactive, apparent power, and power factor • Cable section and voltage drop calculations • Cable ampacity based on IEC 60364-5-52 installation methods • Breaker and fuse selection with overload protection checks • Transformer loading, losses, efficiency, and short-circuit current • Motor current, starting current, torque, and IEC 60034-30-1 efficiency • Grounding, compensation, lighting, energy consumption, unit conversion, and formulas Use ElecCalc when you need a quick engineering estimate, a repeatable calculation flow, or a compact reference while working away from your desk. Support: https://saevaexe.github.io/eleccalc/support.html Privacy Policy: https://saevaexe.github.io/eleccalc/privacy-policy.html Terms of Use: https://saevaexe.github.io/eleccalc/terms.html

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.