kW to HP: How to Convert Kilowatts to Horsepower
Australian spec sheets swap between kilowatts and horsepower without warning, and 1.341 is the number that joins them. Multiply by 1.341 for mechanical horsepower.
hp = kW × 1.341
To convert horsepower back to kilowatts, multiply hp by 0.7457. For example, 5 kW is approximately 6.7 hp.
Quick reference: 1 kW ≈ 1.341 hp, using mechanical horsepower unless otherwise stated.
We’ll work through the formulas, why the two units survive side by side, and what a rating means on a motor, a generator, a solar system, a ute, a bore pump or a portable power station in Australia.
How Do You Convert kW to HP?
Spec sheets pick their own unit and leave you to sort out the rest. One multiplier and your phone’s calculator will do it, which is just as well when you’re squinting at a compliance plate.
Use the kW to HP Conversion Formula
The mechanical horsepower quoted on utes and outboards comes from this formula:
Power (hp) = Power (kW) × 1.34102
To convert kW to mechanical horsepower, take the kW value, multiply it by 1.34102, and label the result as mechanical hp.
Example: A pressure cleaner rated at 2.2 kW:
2.2 × 1.341 = 2.95 hp
So, its power rating is approximately 3 hp.
For a quick kW to hp calculation, multiplying by 1.34 is usually accurate enough for everyday calculations.
Common kW to HP Conversions for Engines
Ratings rarely line up, so a table helps when a bore pump is quoted in horsepower and a ute in kilowatts.
Power (kW) | Mechanical Power (hp) | Metric Power (PS / cv) | Common Real-World Application |
0.75 kW | 1.01 hp | 1.02 PS | Small farm workshop bench grinder or transfer pump |
1 kW | 1.34 hp | 1.36 PS | Small motor or light-duty equipment |
1.5 kW | 2.01 hp | 2.04 PS | Pool pump behind a suburban fence |
2.2 kW | 2.95 hp | 2.99 PS | High-pressure washer or 10A compressor |
3 kW | 4.02 hp | 4.08 PS | Workshop motor or larger water pump |
5 kW | 6.71 hp | 6.80 PS | Larger pump or workshop equipment |
5.5 kW | 7.38 hp | 7.48 PS | Piston compressor in a workshop |
10 kW | 13.41 hp | 13.60 PS | Larger motor or pumping equipment |
11 kW | 14.75 hp | 14.96 PS | Heavy-duty irrigation pump on a broadacre farm |
50 kW | 67.05 hp | 67.98 PS | Compact tractor on a lifestyle block |
100 kW | 134.10 hp | 135.96 PS | Vehicle engine or larger industrial equipment |
110 kW | 147.51 hp | 149.56 PS | 2.0L turbo diesel ute or light commercial van |
150 kW | 201.15 hp | 203.94 PS | Dual-cab 4WD with a 150 kW engine |
200 kW | 268.20 hp | 271.92 PS | V6 turbo diesel ute or a performance wagon |
Convert HP to kW in Reverse
To run it the other way, back into kilowatts, either of these works:
Power (kW) = Power (hp) × 0.7457
or
Power (kW) = Power (hp) ÷ 1.341
For example, a 10 hp motor is approximately:
10 × 0.7457 = 7.46 kW
What Is the Difference Between kW and HP?
Both measure the rate at which work gets done, but they come from different measurement systems and have ended up on different equipment. One sits on your switchboard, the other on your ute’s badge.
Feature | Kilowatt (kW) | Horsepower (hp) |
Measurement System | International System of Units (SI) | Non-SI unit; definition varies by horsepower standard |
Base Definition | 1 kW = 1,000 joules per second | 1 hp = 33,000 foot-pounds per minute |
Common Australian Usage | SI power unit used on equipment specifications | Older power unit still quoted for engines |
Primary Domain | Electrical grids, solar systems, appliances, modern EV specs | Combustion engines, outboards, mechanical pumps |
Equivalence | 1 kW ≈ 1.341 hp (mechanical) | 1 hp (mech) ≈ 0.746 kW |
Kilowatts Measure Power Output
A kilowatt is 1,000 watts, which is 1,000 joules of energy moving each second. It is a decimal multiple of the SI unit of power, the watt, used on appliances, solar gear, motors and many vehicle spec sheets.
Horsepower Measures Mechanical Power
Horsepower is the older unit, and you still see it quoted on engines and anything with a shaft. There are a few different versions of it, and the multiplier moves a little depending on which one the spec sheet was written to.
Mechanical Horsepower (Imperial hp): Defined as 550 foot-pounds per second (roughly 745.7 watts). This standard is used across the UK, the US, and Australian automotive and marine circles.
Metric Horsepower (PS, cv, or ch): Defined as 75 kilogram-force metres per second (roughly 735.5 watts).
The Variance: A European car rated at 200 PS delivers roughly 197 mechanical horsepower (or 147 kW). For day-to-day calculations, the difference is only around 1.4%, but it’s worth keeping in mind when reading German or Japanese engine documentation.
How Is kW Used in Australian Energy Equipment?
In Australia, kilowatts are what get quoted on solar systems, inverters, generators and portable power stations. What that number refers to depends on the gear it’s stamped on, which is where confusion starts.
Solar Systems Use kW to Indicate System Size
Residential solar systems are generally rated according to the combined DC capacity of their panels. A 6.6 kW solar system, for instance, refers to the rated peak output of the panel array under standard test conditions. It’s about the panels, not a February afternoon with cloud coming in. Understanding why solar panels may produce less than their rated wattage helps explain the gap between system size and actual output.
Inverters Use kW to Indicate Power Output
An inverter takes DC from the panels or the battery and turns it into AC for the house. The kW rating is how much AC it can hand over at any one moment, and that’s what decides whether the kettle and the air con can run together.
Generators Use kW to Indicate Available Power
Generator specifications often list both kW (real power) and kVA (apparent power). While kW shows the actual working power available to drive equipment, generators are also strictly current-limited by their kVA rating. For inductive loads like bore pumps, compressors, or air conditioners (which often have a power factor between 0.7 and 0.85), you must ensure the total load doesn’t exceed either the generator’s kW or kVA limits. On site those limits decide if the bore pump starts or trips the generator.
Portable Power Stations Use kW to Indicate AC Output
On a portable power station, the continuous kW rating is the AC load it can run at once. It might be the fridge and the lights together, or one appliance that wants nearly all of it.
The EcoFlow DELTA 3 Max Plus Portable Power Station provides up to 3 kW of continuous AC output, making it suitable for everyday backup and off-grid loads such as refrigerators, cooking appliances, lighting, and other common devices.
The EcoFlow DELTA Pro 3 Portable Power Station increases continuous AC output to 4 kW, making it better suited to higher-demand equipment such as air conditioners, pumps, and power tools.
When choosing one, add up the running wattage of everything you want going at once and put that against the continuous output.
What Should You Check When Comparing Power Ratings?
A single kW or hp figure won’t tell you on its own whether a machine suits the job. You also need to know what that figure measures and what the equipment asks for once it’s working.
Check Whether the Rating Is Input or Output
What an appliance draws from the power point isn’t necessarily what it delivers at the shaft. Energy is lost as heat, through friction and other inefficiencies, so check whether the kW figure on the plate is power consumed or power delivered.
Consider the Equipment's Actual Power Requirements
Anything with a motor in it wants more power to get going than to keep going. Compressors, pumps, air conditioners and plenty of power tools pull several times their running load for a second or two on start-up.
Match the Power Rating to the Application
Buy for the load you’ll actually run, not the biggest number on the shelf. Tally everything that might be running together, find the worst start-up demand of the lot, and leave headroom for the day you add one more thing. The same checks help when choosing a generator size for home backup.
Conclusion
The arithmetic is the easy part of the job. Multiply kilowatts by 1.341 for mechanical horsepower, or hp by 0.7457 to come back. The answer only helps if you know what the number you started with measures.
The judgement comes afterwards, because two machines can wear the same number and mean different things. Check whether you’re reading electrical input, mechanical output or continuous AC output before you pay. Get that right and the number on the box earns its keep. Get it wrong and you find out on a stinking hot afternoon, tank low, when the pump won’t kick over.
FAQ
How Many kW Is a 30 HP Motor?
A 30 hp motor equals roughly 22.37 kW. Multiplying 30 by 0.7457 gives 22.371 kW of mechanical power output.
What's the Difference Between kW and kWh?
Kilowatts (kW) measure the instantaneous rate of power output, whereas kilowatt-hours (kWh) measure the total volume of energy used or stored over time. Running an appliance that draws 2 kW continuously for 3 hours consumes exactly 6 kWh of electrical energy. One tells you how fast, the other how much, and people mix them up constantly.
Do Solar Panels Produce kW or kWh?
Solar panels produce power in kilowatts (kW), which accumulates over daylight hours as energy measured in kilowatt-hours (kWh). For example, a rooftop system producing at an average rate of 4 kW across 5 peak sunlight hours generates 20 kWh of electricity for that day. The kWh total is what lands on the bill.
Why Is a Motor Rated in kW?
Motors carry kW ratings because Australia standardises on the International System of Units (SI). The rating is shaft power, not what the motor pulls off the supply, and staying in metric means you can fold in efficiency and power factor, then size the cable, the circuit breaker and the inverter without converting anything.
Does the kW to HP Conversion Factor Always Stay the Same?
No, the exact multiplier depends on whether you are converting to mechanical horsepower or metric horsepower. Mechanical horsepower uses a multiplier of 1.341, while metric horsepower (PS) uses approximately 1.360. Check which horsepower standard a specification uses before converting.