Tools

HVAC duct size calculator

Size HVAC duct with a Duct Size Calculator App to ensure the correct duct size according to equal friction method, velocity limit and allow user defined size, including IP (CFM) and SI (L/s and m3/hr) units. Tip: Click button “Suggest me” will automatically fill in “user defined” size for you.

HVAC duct size calculator v2.6.1_20250713

HVAC unit converter

Convert engineering units most often found in HVAC system. Tip: Click on the unit you want, then put the value. Or put the value, then click on the unit. Both are work for you.

HVAC unit converter

HVAC duct size calculator SI Unit minimal version v2.0.20250615

Try new version above (HVAC duct size calculator v2.6.x_2025xxxx). However, if you prefer minimal one, please let me know in the comment below or directly e-mail me at jinds2011@gmail.com