Watts to BTU/hour Converter
Enter a value to instantly convert between power units.
Precision4 dp
1 Watt = 3.4121 BTU/hour
Key Formulas
Kilowatt → Horsepower (mech)
hp = kW × 1.34102Horsepower (mech) → Kilowatt
kW = hp × 0.7457Watt → Kilowatt
kW = W × 0.001Kilowatt → Watt
W = kW × 1000Formula
BTU/h = W × 3.41214One watt equals 3.412 BTU per hour. Since 1 BTU = 1055.05585262 J and 1 hour = 3600 s, 1055.05585262 ÷ 3600 = 0.293071 W per BTU/h, so 1 W = 3.41214 BTU/h. Used in HVAC sizing.
Source: NIST SP 811
Frequently Asked Questions
Real-World Examples
1000 W equals 3412 BTU/h — electric heater.
1000 W = 3412 BTU/h
3500 W equals 11,942 BTU/h — central AC.
3500 W = 11942 BTU/h
500 W equals 1706 BTU/h.
500 W = 1706 BTU/h
100 W equals 341 BTU/h.
100 W = 341.2 BTU/h