kW to HP Calculator
1 kilowatt (kW) equals 1.34102 mechanical horsepower (HP). Horsepower was defined by James Watt in the late 18th century as the power required to lift 33,000 pounds one foot in one...
Formula
Source: NIST SP 811, IEC 60072, NEMA MG 1 | Last reviewed: July 26, 2026
Examples
1 kW
= 1.341 hp
1 kW = 1.341 HP -- base conversion
75 kW
= 100.6 hp
75 kW = 100.6 HP -- common industrial motor
0.75 kW
= 1.006 hp
0.75 kW = 1 HP approximately (standard NEMA 1 HP ~ 0.746 kW IEC motor)
200 kW
= 268.2 hp
200 kW = 268.2 HP -- large industrial drive
Quick Reference Table
| kW (IEC) | HP (Mechanical) | Typical Application |
|---|---|---|
| 0.18 | 0.24 | Small fan motor |
| 0.37 | 0.5 | Fractional HP -- small pump |
| 0.75 | 1.01 | ~1 HP -- residential well pump |
| 1.5 | 2.01 | Small compressor |
| 2.2 | 2.95 | ~3 HP -- conveyor motor |
| 4 | 5.36 | ~5 HP -- industrial fan |
| 7.5 | 10.06 | ~10 HP -- hydraulic pump |
| 15 | 20.12 | ~20 HP -- air compressor |
| 22 | 29.5 | ~30 HP -- process pump |
| 37 | 49.6 | ~50 HP -- large pump drive |
| 55 | 73.8 | ~75 HP -- industrial compressor |
| 75 | 100.6 | ~100 HP -- large industrial motor |
| 90 | 120.7 | ~125 HP -- heavy conveyor |
| 132 | 177 | ~175 HP -- mine ventilation fan |
| 200 | 268.2 | ~250 HP -- large drive |
| 315 | 422.4 | ~400 HP -- heavy industrial |
| kW | HP |
|---|---|
| 0.5 | 0.67 |
| 1 | 1.34 |
| 3 | 4.02 |
| 5 | 6.71 |
| 10 | 13.41 |
| 25 | 33.53 |
| 50 | 67.05 |
| 100 | 134.1 |
| 250 | 335.3 |
| 500 | 670.5 |
| 1000 | 1341 |
| 5000 | 6705 |
Popular Conversions
Quick answers for the most-searched kW to hp values.
75 kW to HP
75 kW = 100.6 hp
The most common industrial motor conversion. 75 kW (100 HP) is the standard large motor size for pumps, compressors, and fans worldwide. Used in municipal water treatment, HVAC central plants, and heavy manufacturing.
1 kW to HP
1 kW = 1.341 hp
Base conversion: 1 kW = 1.341 HP. Useful for comparing US and European appliance and small motor ratings. A 1 kW microwave or space heater draws power equivalent to 1.34 HP.
0.75 kW to HP
0.75 kW = 1.006 hp
The closest IEC motor size to 1 HP. A 0.75 kW motor is the standard replacement for a 1 HP NEMA motor. The 0.6% overshoot (1.006 vs 1.000 HP) is well within NEMA MG 1 service factor tolerance.
2.2 kW to HP
2.2 kW = 2.95 hp
Common IEC motor size ~ 3 HP. Used for conveyors, small pumps, and HVAC fans. The 2.2 kW = 2.95 HP motor is the European equivalent for replacing a 3 HP NEMA motor.
7.5 kW to HP
7.5 kW = 10.06 hp
7.5 kW ~ 10 HP. Common hydraulic pump and compressor motor size in both IEC and NEMA systems. At 460V 3-phase, draws approximately 11 FLA per NEC tables.
15 kW to HP
15 kW = 20.12 hp
15 kW ~ 20 HP. Standard process pump and industrial fan motor. At this size, the efficiency difference between IE3 (Premium) and IE4 (Super Premium) can be 1-3%, saving hundreds of dollars annually in electricity.
Where is this used?
(1) Electric motor specification and replacement: European and Asian motors carry IEC nameplate ratings in kW (IEC 60034-1), while North American motors use NEMA HP (NEMA MG 1).
A maintenance engineer replacing a failed 55 kW German-made pump motor must find a NEMA replacement.
Converting 55 kW x 1.34102 = 73.8 HP points to a 75 HP NEMA motor as the nearest equivalent.
The reverse is equally common: a North American OEM exporting a machine with a 200 HP motor to a European customer must label the motor as 149 kW per EU Machinery Directive documentation.
(2) International pump and compressor skid procurement: a project specification typically lists motor requirements in one unit system.
An engineer reviewing a bid from an Italian manufacturer quoting a 132 kW motor for a centrifugal compressor skid converts to 177 HP and compares against the 175 HP specification baseline.
The 2 HP margin supports the bid without requiring an upsized motor.
(3) Generator and engine sizing: diesel generator sets in international markets are rated in kW (prime power per ISO 8528), but in North American agricultural, construction, and fire pump markets, engine power is expressed in HP.
A 500 kW generator's prime mover is a 670 HP diesel engine (500 / 0.746 / 0.93 drivetrain efficiency).
Converting between kW electrical output and HP mechanical input requires the alternator efficiency (~93-96%) on top of the unit conversion.
(4) Variable frequency drive (VFD) selection: VFDs from global manufacturers (ABB, Siemens, Danfoss, Rockwell) are cataloged in kW output ratings.
A 100 HP fan motor requires a VFD with at least 74.6 kW output.
The engineer selects a 75 kW drive -- the standard catalog size.
Undersizing by using a 55 kW drive (thinking 55 kW handles 100 HP) would cause immediate overload trip.
(5) Electric vehicle motor ratings: modern EVs specify motor power in kW -- the Tesla Model 3 base motor is 211 kW, equivalent to 283 HP.
Automotive journalists and consumers in North America still think in HP, making this conversion essential for product comparison.
The Ford F-150 Lightning's 452 kW dual-motor equals 606 HP.
(6) HVAC chiller and compressor comparative analysis: European chiller packages quote compressor motor ratings in kW electrical input, while US catalogues quote compressor HP.
A 300 kW compressor (402 HP) in a European centrifugal chiller bid must be compared against a US bid offering a 400 HP compressor for apples-to-apples efficiency evaluation (kW/ton, COP, IPLV).
(7) Mining and heavy industrial equipment: mine hoists, crushers, and conveyor drives routinely exceed 1,000 kW (1,341 HP).
A 2,500 kW ball mill drive at a copper mine in Chile (rated by the European OEM in kW) must be communicated to the North American operations team in HP for their spares inventory and maintenance planning.
(8) Marine and offshore: ship propulsion motors and thrusters are universally specified in kW under IMO and classification society rules.
However, many auxiliary pumps, fans, and compressors are sourced globally and carry mixed nameplates.
A 7,500 kW azimuth thruster on an offshore supply vessel delivers 10,058 HP at the propeller shaft.
Real-World Usage Scenarios
International pump skid procurement: Bridging the specification gap
Maria, a project engineer at a Texas petrochemical plant, is procuring a chemical injection pump skid. The project specification requires a 50 HP minimum pump driver per the mechanical equipment schedule. Three international vendors submit bids: a German manufacturer quotes a 37 kW motor, an Italian vendor proposes a 45 kW motor, and a US fabricator offers a 50 HP motor directly. Maria converts all to HP for comparison: 37 kW x 1.341 = 49.6 HP (fails the 50 HP minimum), 45 kW x 1.341 = 60.3 HP (exceeds, but costs 18% more), and the US unit at exactly 50 HP. Maria flags the 37 kW German bid as non-compliant. The vendor confirms the next standard IEC frame (45 kW) is the correct substitution. The German bid is revised with the 45 kW motor, cost added, and re-evaluated. Without the unit conversion check, an underpowered pump skid would have been purchased, installed, and discovered only during commissioning when it could not meet the design flow at the required discharge pressure.
VFD replacement for a cooling tower fan: Avoiding the 0.6 HP trap
Carlos, a maintenance supervisor at a pharmaceutical plant, faces a failed 100 HP NEMA motor on a cooling tower fan. The only available spare in the warehouse is a European 75 kW (100.6 HP) IEC motor purchased for a different project. The existing VFD is nameplate-rated for 100 HP output (75 kW continuous, 82.5 kW for 60 seconds at 110% overload). Carlos calculates: 75 kW x 1.341 = 100.6 HP -- that is 0.6 HP above the VFD nameplate. Rather than risking a drive overload trip during the hottest summer days when the fan runs at full speed, Carlos checks the actual operating data. The VFD logs show the fan has never exceeded 89% speed (approximately 70% power per the fan affinity laws). At the real operating point: 75 kW x 0.70 x 1.341 = 70.4 HP actual draw -- well within the VFD rating. The motor is installed, the VFD's current limit is set to match the 75 kW FLA, and the cooling tower returns to service the same evening. The conversion was essential not just for motor-to-motor comparison but for verifying the entire drive train compatibility.
EV fleet comparison for a corporate sustainability report
Jennifer, a fleet manager for a logistics company, needs to compare three electric delivery vans for the annual sustainability report to shareholders. The European van (Mercedes eSprinter) is rated at 150 kW peak motor power. The US van (Ford E-Transit) is marketed as 266 HP. The Chinese van (BYD) is rated at 130 kW continuous and 180 kW peak. To present a uniform comparison table in HP for the US-based board, Jennifer converts: 150 kW x 1.341 = 201 HP (Mercedes peak), 266 HP (Ford, no conversion needed), and 180 kW x 1.341 = 241 HP (BYD peak). She adds a column for continuous power too: 130 kW = 174 HP (BYD continuous, vs. the Mercedes' 100 kW / 134 HP continuous rating found in the detailed spec sheet). The board now has a consistent apples-to-apples comparison to evaluate total cost of ownership per HP of fleet capacity. The conversion revealed that the BYD, despite lower peak kW, has higher continuous power delivery -- important for highway driving duty cycles.
Common Mistakes to Avoid
Using metric HP (PS) instead of mechanical HP
Metric horsepower (PS, Pferdestarke, or CV per DIN 66036) is 735.4988 W -- approximately 1.4% less than mechanical HP (745.6999 W). A 100 kW motor converts to 134.1 mechanical HP but 135.9 PS. If a European datasheet quotes '100 kW (136 CV),' and an American engineer uses 1 kW = 1.341 HP to verify, the 134 HP vs. 136 mismatch creates unnecessary confusion. The error is 2 HP (1.5 kW). Across a fleet of 200 motors averaging 50 kW each, the cumulative error is 200 x (50 x 0.02012) = 201 HP or 150 kW of misattributed capacity -- enough to require an additional transformer. Always check whether the source specification is using mechanical HP (NEMA, US, UK) or PS (continental Europe, Japan). Automotive specs in Europe, Japan, and Korea almost universally use PS. Industrial motor specs under IEC 60072 use kW and the conversion to mechanical HP per NIST.
Assuming nameplate kW is electrical input power
An electric motor nameplate kW is always the mechanical output power at the shaft (per IEC 60034-1 and NEMA MG 1), not the electricity consumed. A 75 kW motor produces 75 kW at the shaft but draws approximately 83 kW from the supply at 90% efficiency. The error chain: an engineer converts 75 kW to 100.6 HP, then sizes the generator at 100.6 HP x 0.746 = 75 kW of electrical capacity -- but the actual electrical draw is 83 kW, undersizing the generator by 8 kW (10.7%). For a single motor, this causes overload trips. For a panel with ten 75 kW motors, the cumulative under-sizing is 80 kW -- requiring an entire additional generator module in a critical backup power system. Always use motor full-load amps from the nameplate or NEC Table 430.250 for electrical system design. The mechanical kW/HP rating is for shaft sizing, coupling selection, and driven equipment matching only.
Converting motor electrical input kW to HP with the unit factor
A common field shortcut: measuring a running motor's electrical input from a power meter (say 90 kW), then multiplying by 1.341 to get '120.7 HP -- this motor is overloaded for its 100 HP nameplate.' This is wrong on two counts. First, the 90 kW input at 92% efficiency delivers 82.8 kW shaft = 111 HP -- the motor IS overloaded by 11%, but not by the 20.7 HP the shortcut suggests. Second, the motor may have a 1.15 service factor (per NEMA MG 1) allowing 15% continuous overload above nameplate HP. The correct check: measure electrical input kW, multiply by motor efficiency (from nameplate or IEEE 112 test data), then convert the resulting shaft kW to HP, and compare against nameplate HP x service factor. The chain is: Input kW x Efficiency = Shaft kW, then Shaft kW x 1.341 = Shaft HP. Skipping the efficiency step inflates apparent motor load by 8-15%, triggering false overload alarms and unnecessary equipment replacement.
Industry Standards Referenced
Frequently Asked Questions
What is the formula to convert kW to HP?
HP = kW x 1.34102. This is the standard mechanical horsepower conversion based on 1 HP = 745.6999 watts = 0.7456999 kW per NIST SP 811. For quick mental math, multiply kW by 1.34, or add one-third: 75 kW ~ 75 + 25 = 100 HP (actual: 100.6 HP). For precise engineering work, use 1.34102 with six significant figures. The derivation: 1 HP = 33,000 ft-lbf/min. 1 ft = 0.3048 m, 1 lbf = 4.44822 N. So 1 HP = 33,000 x 0.3048 x 4.44822 / 60 = 745.6999 N-m/s = 745.6999 W. Therefore 1 kW = 1,000 / 745.6999 = 1.34102209 HP.
How many HP is 1 kW?
1 kW = 1.34102 HP. In round numbers: 1 kW ~ 1.34 HP. This means a 1 kW motor is slightly more powerful than a 1 HP motor (which is 0.746 kW). When replacing a 1 HP motor with a kW-rated equivalent, the closest IEC size is 0.75 kW (1.006 HP). The 0.75 kW motor has essentially identical mechanical output to the 1 HP motor -- the 0.006 HP difference is within manufacturing tolerances.
How many HP is 75 kW?
75 kW = 100.6 HP. This is one of the most common industrial motor sizes -- a 75 kW (100 HP) motor is widely used for large pumps, compressors, and fans in water treatment plants, HVAC chiller plants, and manufacturing facilities worldwide. The 75 kW IEC motor is the standard cross-reference for NEMA 100 HP. Applications include: cooling tower fans (15-100 HP typical), chilled water pumps, air compressor main drives, hydraulic power units, and large conveyor systems. At 480V 3-phase, a 100 HP motor draws approximately 124 FLA (NEC Table 430.250).
Are kW and HP measuring the same thing?
Yes. Both kW (kilowatts) and HP (horsepower) are units of power -- the rate at which work is done or energy is transferred. 1 kW = 1,000 joules per second. 1 HP = 550 ft-lbf per second = 33,000 ft-lbf per minute. They measure identical physical quantities. The difference is only the unit system: kW is SI (metric), HP is US customary. However, note the difference between mechanical HP (745.7 W), metric HP or PS (735.5 W), boiler HP (9,809.5 W), and hydraulic HP (flow x pressure / 1714). This calculator uses mechanical HP per NIST SP 811. For automotive PS conversion, multiply kW by 1.35962 instead of 1.34102.
Is the kW to HP conversion the same for electric motors and engines?
The unit conversion factor (1 kW = 1.34102 HP) is identical regardless of what the power source is. However, the context changes: for electric motors, the kW rating on a nameplate is the mechanical output power (shaft power), not the electrical input power. A 75 kW motor produces 75 kW (100.6 HP) at the shaft -- but consumes approximately 83-88 kW of electricity depending on efficiency (typically 90-96% for industrial motors per NEMA MG 1 Table 12-10). For internal combustion engines (SAE J1349), the HP rating is also shaft output measured at the flywheel after deducting accessory loads. SAE net HP for a 200 HP truck engine is comparable to 149 kW shaft output. The conversion between shaft power units is independent of the prime mover type.
What are the standard IEC motor kW sizes that correspond to NEMA HP?
IEC standard kW ratings (per IEC 60072) map approximately to NEMA HP: 0.37 kW ~ 1/2 HP, 0.75 kW ~ 1 HP, 1.5 kW ~ 2 HP, 2.2 kW ~ 3 HP, 4 kW ~ 5 HP, 5.5 kW ~ 7.5 HP, 7.5 kW ~ 10 HP, 11 kW ~ 15 HP, 15 kW ~ 20 HP, 18.5 kW ~ 25 HP, 22 kW ~ 30 HP, 30 kW ~ 40 HP, 37 kW ~ 50 HP, 45 kW ~ 60 HP, 55 kW ~ 75 HP, 75 kW ~ 100 HP, 90 kW ~ 125 HP, 110 kW ~ 150 HP, 132 kW ~ 175 HP, 160 kW ~ 200 HP, 200 kW ~ 250 HP, 250 kW ~ 300 HP, 315 kW ~ 400 HP, 355 kW ~ 475 HP, 400 kW ~ 500 HP.
Reviewed for accuracy
Reviewed against NIST SP 811 mechanical horsepower definition, IEC 60072 standard motor ratings, and NEMA MG 1 motor nameplate conventions · Last reviewed: July 26, 2026
All calculations are for reference only. Always verify with manufacturer data and a qualified engineer for critical applications. Learn about our editorial process.