Horsepower to Gigawatts
Convert horsepower to gigawatts instantly — one horsepower is 7.457e-07 gigawatts.
| Horsepower | Gigawatts |
|---|---|
| 1 hp | 7.457e-07 GW |
| 2 hp | 1.4914e-06 GW |
| 3 hp | 2.2371e-06 GW |
| 5 hp | 3.7285e-06 GW |
| 10 hp | 7.457e-06 GW |
| 25 hp | 1.86425e-05 GW |
| 50 hp | 3.7285e-05 GW |
| 100 hp | 7.457e-05 GW |
How to use
- Enter a value in the Horsepower field.
- The Gigawatts figure appears immediately — no button to press.
- Typing in the Gigawatts field converts back to Horsepower the same way.
- Use the reference table for the values that come up most often.
Horsepower to Gigawatts formula
The factor from horsepower to gigawatts is 7.45699872e-07.
GW = hp × 7.45699872e-07
Why this factor: the horsepower and the gigawatt are both defined against the watt, so dividing one definition by the other gives 7.45699872e-07 directly. Both definitions are set out in full below.
To go the other way, divide by 7.45699872e-07 — or use the Gigawatts to Horsepower converter, which is the same calculation reversed.
Worked example
Start with 150 hp. Multiply by 7.45699872e-07 to get 0.000112 GW.
150 hp × 7.45699872e-07 = 0.000112 GW
The converter above does this for any value you type, in either direction.
What is a horsepower?
Mechanical horsepower is the traditional English-speaking unit of engine power.
Definition: Defined as 550 foot-pounds per second, which is about 745.700 watts.
Where it is used: US and UK car, motorcycle and small-engine power ratings.
Worth knowing: Distinct from metric horsepower (PS), which is about 1.4% smaller — so the same engine scores slightly higher in PS than in hp.
What is a gigawatt?
A gigawatt is one billion watts — the scale of national grids and large nuclear plants.
Definition: Exactly 1×10⁹ watts.
Where it is used: National electricity demand, total installed renewable capacity, and large nuclear reactor output.
Horsepower vs Gigawatts
The horsepower is an imperial unit while the gigawatt is a metric unit. That is why the factor between them is not a round number: the two systems were defined independently and only later tied together by exact agreement.
Frequently asked questions
How many gigawatts are in a horsepower?
One horsepower equals 7.45699872e-07 gigawatts.
What is the formula to convert horsepower to gigawatts?
Multiply the number of horsepower by 7.45699872e-07. To reverse it, divide by 7.45699872e-07 instead.
How do I convert gigawatts back to horsepower?
Divide by 7.45699872e-07, which is the same as multiplying by 1341022.09.
How many gigawatts are in 10 horsepower?
10 hp works out to 7.457e-06 GW.
Is there anything to watch out for with horsepower?
Distinct from metric horsepower (PS), which is about 1.4% smaller — so the same engine scores slightly higher in PS than in hp.
How is the horsepower defined?
Defined as 550 foot-pounds per second, which is about 745.700 watts.