PT Ductulator

This is the easiest duct sizing calculator you’ll ever use.

PT Ductulator is a simple, modern duct sizing tool for HVAC technicians, designers, and students. No spinning wheels, no cluttered screens—just clean inputs and instant, easy-to-read results.

Whether you’re on a rooftop, in an attic, or at the design desk, Ductulator helps you make fast, confident decisions about duct size, airflow, and comfort.
Why it feels so easy
- Straightforward layout – Type in what you know, see what you need. No hunting through menus.
- Big, readable numbers – Designed for real job sites, not just a desk.
- Instant feedback – Adjust a value and see airflow, friction, and velocity update right away.

What you can do with it
- Size round and rectangular ducts
-Enter airflow and your target friction or velocity and get recommended duct sizes in seconds.
- Compare duct options
- See how changing size affects velocity and friction so you can avoid noise, hot spots, and high static.
- Get equivalent round sizes
- Convert rectangular duct dimensions to an equivalent round size to compare and explain choices.
- Work anywhere
All calculations run offline on your device. Perfect for basements, rooftops, and new construction sites.

Built for HVAC pros
Use Ductulator to:
- Double-check proposed duct sizes before installation
- Verify existing systems during service calls
- Teach apprentices how size, airflow, and friction relate
- Have clearer conversations with homeowners, builders, and inspectors

If you work with ductwork, this is the ductulator you’ll actually want to use—fast, simple, and always in your pocket.