How do you convert BTU per second to watts?

To convert BTU per second to watts, multiply the power in BTU/s by 1055.056. One BTU per second is exactly equal to 1055.056 watts: W = BTU/s × 1055.056.

How do you convert watts to BTU per second?

To convert watts to BTU per second, divide the power in watts by 1055.056. The formula is: BTU/s = W ÷ 1055.056.

What is BTU per second used for?

BTU per second is a power unit commonly used in heating and cooling, combustion, and thermodynamics to express how quickly energy is transferred as heat. Engineers often convert BTU/s to watts to compare with SI-based specifications.

BTU per Second to Watts Converter

Q: How many watts are in 1 BTU per second?

1 BTU per second is equal to 1055.056 watts. This is based on the definition that 1 BTU (International Table) is 1055.056 joules and 1 watt is 1 joule per second.

Convert power between BTU per second (Btu/s) and watts (W) instantly, with high precision and clear formulas.

BTU/s ⇄ Watts Conversion

BTU per second to watts

Power in BTU per second (Btu/s)

Btu/s

Result in watts (W)

Formula: W = Btu/s × 1055.056

Watts to BTU per second

Power in watts (W)

Result in BTU per second (Btu/s)

Btu/s

Formula: Btu/s = W ÷ 1055.056

Using BTU (International Table). 1 Btu/s = 1055.056 W.

BTU per Second to Watts Formula

From BTU per second to watts

W = P_Btu/s × 1055.056

where:

P_Btu/s is power in BTU per second
W is power in watts
1 BTU (IT) = 1055.056 joules, and 1 W = 1 J/s

From watts to BTU per second

P_Btu/s = W ÷ 1055.056

Worked examples

Example 1: 1 Btu/s to watts
W = 1 × 1055.056 = 1055.056 W
Example 2: 2.5 Btu/s to watts
W = 2.5 × 1055.056 ≈ 2637.64 W
Example 3: 2000 W to BTU/s
Btu/s = 2000 ÷ 1055.056 ≈ 1.896 Btu/s

Quick Reference Table

BTU/s	Watts (W)

Values are rounded to 3 decimal places for readability.

What are BTU per second and watts?

Both BTU per second (Btu/s) and watts (W) are units of power, meaning the rate at which energy is transferred or converted.

BTU per second (Btu/s) – power expressed in British Thermal Units per second, often used in heating and combustion contexts.
Watt (W) – the SI unit of power, equal to one joule per second. It is the standard unit used in most engineering and electrical specifications.

Because most technical datasheets use watts or kilowatts, it is common to convert legacy or imperial heat-rate data from BTU/s to W.

BTU/s vs BTU/hr vs watts

You will also see BTU per hour (Btu/hr) in HVAC and boiler ratings. Note that:

1 Btu/s = 3600 Btu/hr
1 Btu/hr ≈ 0.293071 W
1 Btu/s = 1055.056 W (exact, using BTU_IT)

If your data is in BTU/hr, convert to watts using 1 Btu/hr ≈ 0.293071 W, or divide watts by 0.293071 to get BTU/hr.

Precision and BTU definitions

This converter uses the International Table BTU (BTU_IT), defined as exactly 1055.056 joules. That is the most common definition in engineering and thermodynamics.

Other BTU definitions (e.g., thermochemical BTU) differ slightly, but for almost all practical engineering and HVAC work, BTU_IT is appropriate and the numerical difference is negligible.

FAQ

How many watts are in 1 BTU per second?

1 BTU per second is exactly 1055.056 watts when using the International Table BTU. That is equivalent to about 1.055 kW.

How do I convert BTU per second to kilowatts?

First convert BTU/s to watts, then divide by 1000:

kW = (Btu/s × 1055.056) ÷ 1000

For example, 3 Btu/s ≈ (3 × 1055.056) ÷ 1000 ≈ 3.165 kW.

Is BTU per second the same as BTU per hour?

No. BTU per second is 3600 times larger than BTU per hour:

1 Btu/s = 3600 Btu/hr
1 Btu/hr = 1/3600 Btu/s ≈ 0.00027778 Btu/s

When should I use BTU/s vs watts?

Use watts or kilowatts for most modern engineering, electrical, and HVAC calculations, since they are SI units and integrate cleanly with other SI-based formulas. BTU/s is mainly encountered in older literature, combustion calculations, or when working with imperial-based heat-rate data.