About Heater Size Calculator
Calculate space heater wattage and BTU heating requirements for any room.. Designed for accurate, instantaneous calculations with zero wait time.
Formula
Wattage = Room Area (sq ft) × 10 Watts (for standard 8ft ceilings)
Example Calculation
A 150 sq ft room requires a 1,500 Watt electric heater (~5,118 BTU/hr).
How to Use
- Enter your values into the form fields above.
- The calculation updates immediately in real time.
- Inspect the main summary and secondary breakdowns below.