How many horsepower are in 1 watt?

1 W equals 0.00134102209 hp. This is an exact conversion factor defined by NIST.

How do I convert watts to horsepower?

Multiply the value in W by the conversion factor. For example, 10 W = 0.0134102209 hp. Use our calculator above for instant results.

Is the watts to horsepower conversion exact?

Yes, this conversion is mathematically exact based on the international definition of these units (NIST SP 811).

Can I convert watts to horsepower offline?

Yes! OmniConvert runs entirely in your browser — no internet connection needed after the page loads. Your data never leaves your device, ensuring complete privacy.

What is the difference between watts and horsepower?

Watts (W) and Horsepower (hp) are both units of power but belong to different measurement systems. 1 W = 0.00134102209 hp. Use the converter above to switch between them instantly.

Watts to Horsepower (W → hp) — Free Online Converter

W → hp Reference Table

W	hp
0.001 W	0.00000134102209 hp
0.002 W	0.000002682044179 hp
0.003 W	0.000004023066269 hp
0.004 W	0.000005364088358 hp
0.005 W	0.000006705110448 hp
0.006 W	0.000008046132538 hp
0.007 W	0.000009387154627 hp
0.008 W	0.00001072817672 hp
0.009 W	0.00001206919881 hp
0.01 W	0.0000134102209 hp
0.02 W	0.00002682044179 hp
0.03 W	0.00004023066269 hp
0.04 W	0.00005364088358 hp
0.05 W	0.00006705110448 hp
0.06 W	0.00008046132538 hp
0.07 W	0.00009387154627 hp
0.08 W	0.0001072817672 hp
0.09 W	0.0001206919881 hp
0.1 W	0.000134102209 hp
0.2 W	0.0002682044179 hp
0.3 W	0.0004023066269 hp
0.4 W	0.0005364088358 hp
0.5 W	0.0006705110448 hp
0.6 W	0.0008046132538 hp
0.7 W	0.0009387154627 hp
0.8 W	0.001072817672 hp
0.9 W	0.001206919881 hp
1 W	0.00134102209 hp
1.5 W	0.002011533134 hp
2 W	0.002682044179 hp
2.5 W	0.003352555224 hp
3 W	0.004023066269 hp
3.5 W	0.004693577314 hp
4 W	0.005364088358 hp
4.5 W	0.006034599403 hp
5 W	0.006705110448 hp
5.5 W	0.007375621493 hp
6 W	0.008046132538 hp
6.5 W	0.008716643582 hp
7 W	0.009387154627 hp
7.5 W	0.01005766567 hp
8 W	0.01072817672 hp
8.5 W	0.01139868776 hp
9 W	0.01206919881 hp
9.5 W	0.01273970985 hp
10 W	0.0134102209 hp
11 W	0.01475124299 hp
12 W	0.01609226508 hp
13 W	0.01743328716 hp
14 W	0.01877430925 hp
15 W	0.02011533134 hp
16 W	0.02145635343 hp
17 W	0.02279737552 hp
18 W	0.02413839761 hp
19 W	0.0254794197 hp
20 W	0.02682044179 hp
25 W	0.03352555224 hp
30 W	0.04023066269 hp
35 W	0.04693577314 hp
40 W	0.05364088358 hp
45 W	0.06034599403 hp
50 W	0.06705110448 hp
55 W	0.07375621493 hp
60 W	0.08046132538 hp
65 W	0.08716643582 hp
70 W	0.09387154627 hp
75 W	0.1005766567 hp
80 W	0.1072817672 hp
85 W	0.1139868776 hp
90 W	0.1206919881 hp
95 W	0.1273970985 hp
100 W	0.134102209 hp
120 W	0.1609226508 hp
125 W	0.1676277612 hp
130 W	0.1743328716 hp
140 W	0.1877430925 hp
150 W	0.2011533134 hp
160 W	0.2145635343 hp
175 W	0.2346788657 hp
180 W	0.2413839761 hp
200 W	0.2682044179 hp
225 W	0.3017299702 hp
250 W	0.3352555224 hp
275 W	0.3687810746 hp
300 W	0.4023066269 hp
350 W	0.4693577314 hp
400 W	0.5364088358 hp
450 W	0.6034599403 hp
500 W	0.6705110448 hp
600 W	0.8046132538 hp
700 W	0.9387154627 hp
750 W	1.005766567 hp
800 W	1.072817672 hp
900 W	1.206919881 hp
1000 W	1.34102209 hp
1200 W	1.609226508 hp
1250 W	1.676277612 hp
1500 W	2.011533134 hp
1750 W	2.346788657 hp
2000 W	2.682044179 hp
2500 W	3.352555224 hp
3000 W	4.023066269 hp
4000 W	5.364088358 hp
4500 W	6.034599403 hp
5000 W	6.705110448 hp
6000 W	8.046132538 hp
7000 W	9.387154627 hp
7500 W	10.05766567 hp
8000 W	10.72817672 hp
9000 W	12.06919881 hp
10000 W	13.4102209 hp
15000 W	20.11533134 hp
20000 W	26.82044179 hp
25000 W	33.52555224 hp
50000 W	67.05110448 hp
75000 W	100.5766567 hp
100000 W	134.102209 hp

Values based on NIST SP 811 conversion factors

Why Convert Watts to Horsepower?

Converting between watts (W) and horsepower (hp) is one of the most common power conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert W to hp saves time and prevents errors.

Power conversions (W to hp) are essential for automotive enthusiasts, electrical engineers, and athletes. Car buyers frequently convert horsepower to kilowatts to compare engine performance across international brands. In electrical engineering, sizing generators and motors requires consistent power units to prevent overloads and ensure compatibility. Cyclists and rowers use power meters to track output in watts, converting these figures to estimate calorie burn or compare efforts. Misinterpreting power ratings can result in buying underpowered equipment or damaging electrical systems, highlighting the need for accurate conversion tools.

How to Convert Watts to Horsepower

To convert watts to horsepower, use the following formula:

hp = W × 0.00134102209

Example: 1 W = 0.00134102209 hp

For example, 5 W = 0.006705110448 hp, 10 W = 0.0134102209 hp, and 100 W = 0.134102209 hp. For larger values, 1000 W = 1.34102209 hp. Conversely, 1 hp = 745.6998716 W. Our calculator above performs this conversion instantly with full precision — no rounding errors.

Common Use Cases

Exactly one mechanical horsepower: 746 W = 1.000402479 hp
A microwave oven at full power: 1000 W = 1.34102209 hp
An electric kettle: 2000 W = 2.682044179 hp
A professional cyclist's sustained output: 100 W = 0.134102209 hp

Common Mistakes to Avoid

kW vs kWh: kW is power (rate), kWh is energy (total used).
HP variations: Mechanical HP (~745.7W) vs Metric HP (~735.5W).
Apparent Power: Watts vs Volt-Amps (VA) differ due to power factor.

Pro Tips

LED bulbs: A 10W LED replaces a 60W incandescent (saves energy).
Appliance labels: Check the back label for Wattage to avoid overloading strips.
Solar panels: Ratings are 'Peak Watts' (ideal conditions), expect less in reality.

What is a Watt?

The watt (W) is the SI derived unit of power. Defined as one joule per second. Named after James Watt.

Watts are used universally to measure the rate of energy transfer, commonly for light bulbs, electronics, and small appliances.

What is a Horsepower?

Horsepower (hp) is a unit of power. Mechanical horsepower is about 745.7 watts, while metric horsepower is roughly 735.5 watts.

Horsepower is the traditional unit for measuring the power of car engines and electric motors, particularly in the automotive industry.

Watts → Horsepower

Watts to Horsepower Formula