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Convert Watts to BTU per hour

1 watt is 3.412142 BTU/h. One watt is exactly 3.41214163313 BTU per hour.

One watt is 3.4121416 BTU per hour. To convert watts to BTU per hour, multiply by 3.4121416; to go the other way, divide by 3.4121416 or multiply by 0.29307107. The factor is exact rather than rounded: it follows from NIST Special Publication 811. The SI unit: one joule every second.

Factor checked against the defining standard · How we check

BTU per hour
3.412142 BTU/h
Watts × 3.4121416
value * 3.412141633133.412 BTU/h

1 watt in every power unit

UnitValueExact factor
horsepower0.00134102209 hp× 0.0013410220896
metric horsepower0.001359621617 PS× 0.0013596216173
watts (as entered)1 W
kilowatts0.001 kW× 0.001
megawatts0.000001 MW× 0.000001
BTU per hour3.412141633 BTU/h× 3.41214163313

Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.

How do you convert watts to BTU per hour?

  1. 1.Take the measurement in watts.
  2. 2.Multiply by 3.4121416 — that is how many BTU per hour fit in one watt.
  3. 3.To go back the other way, divide by 3.4121416, or multiply by 0.29307107.

Worked example: 25 watts to BTU per hour

Formula
W × 3.4121416 = BTU/h
Arithmetic
25 × 3.4121416 = 85.303541 BTU/h
Answer
25 W = 85.303541 BTU/h

The factor is rounded for display; the figure above is computed from the full value.

Watts to BTU per hour conversion table

WattsBTU per hour
1 W3.412142 BTU/h
2 W6.824283 BTU/h
3 W10.236425 BTU/h
4 W13.648567 BTU/h
5 W17.060708 BTU/h
6 W20.47285 BTU/h
7 W23.884991 BTU/h
8 W27.297133 BTU/h
9 W30.709275 BTU/h
10 W34.121416 BTU/h
12 W40.9457 BTU/h
15 W51.182124 BTU/h
20 W68.242833 BTU/h
25 W85.303541 BTU/h
50 W170.607082 BTU/h
100 W341.214163 BTU/h
200 W682.428327 BTU/h
300 W1,023.64249 BTU/h
500 W1,706.070817 BTU/h
1000 W3,412.141633 BTU/h
2000 W6,824.283266 BTU/h
5000 W17,060.708166 BTU/h
10000 W34,121.416331 BTU/h

What is a watt?

The SI unit: one joule every second. A watt is a rate, not an amount, which is the distinction between it and the watt-hour on your electricity bill.

What is a BTU per hour?

The rate US heating and air conditioning is sold in. A 12,000 BTU/h unit is one "ton" of cooling and about 3.5 kilowatts of heat moved.

How many BTU per hour are in a watt?

One watt is 3.4121416 BTU per hour. Going the other way, one BTU per hour is 0.29307107 watts. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.

Every power unit here

UnitSymbolOne of these is
Horsepowerhp745.69987 watt
Metric horsepowerPS735.49875 watt
WattsWthe base unit
KilowattskW1000 watt
MegawattsMW1000000 watt
BTU per hourBTU/h0.29307107 watt

Source: NIST Special Publication 811 — mechanical horsepower is 550 ft·lbf/s exactly

Questions people actually ask

How many BTU per hour are in a watt?
3.4121416. The rate US heating and air conditioning is sold in. A 12,000 BTU/h unit is one "ton" of cooling and about 3.5 kilowatts of heat moved.
How do I convert BTU per hour back to watts?
Divide by 3.4121416, or multiply by 0.29307107 — they are the same operation.

Other power conversions

BTU per hour to watts — the same conversion the other way.