Power Converter Online: Convert Watts, kW, Horsepower and BTU/h Free
CodexFuse Team · 2026-11-04T01:06:25.711Z · 9 min read min read
Convert watts, kilowatts, horsepower, BTU/h and dBm instantly with CodexFuse's free power converter — plus a worked generator-sizing example.
A power converter is an online tool that translates a power value from one unit to another — watts to kilowatts, kilowatts to horsepower, horsepower to BTU per hour — instantly and without manual arithmetic. If you have ever stared at a motor plate rated in horsepower while your generator is rated in kilowatts, you already know why one exists: the numbers describe the same physical quantity, but the units refuse to match.
Power is the rate at which energy is used or produced, measured in watts. Every other unit — kilowatts, horsepower, BTU per hour, dBm — is just a different scale for the same thing. The trouble starts when two suppliers or two countries use different scales, and a wrong conversion means an undersized generator or a cooling system that cannot keep up.
Why do power units cause so many expensive mistakes?
Power units cause expensive mistakes because the same value looks harmless in one unit and alarming in another, and because horsepower has two definitions. A 150 PS European engine is not a 150 hp American engine — it is about 148 hp — and a 12,000 BTU/h air conditioner is not a 12 kW heater, it is roughly a 3.5 kW one.
The most common mix-ups happen in four places: generator shopping (horsepower versus kilowatts), air conditioning (BTU/h versus watts), cross-market vehicle comparisons (PS versus hp), and radio work, where dBm looks like just another unit but is logarithmic — doubling the watts only adds about 3 dBm.
What units does a power converter actually convert?
A good power converter covers the units people genuinely meet: watt (W), milliwatt (mW), kilowatt (kW), megawatt (MW), gigawatt (GW), mechanical horsepower (hp), metric horsepower (PS), BTU per hour, foot-pound per second, and dBm. CodexFuse's power converter covers all ten and shows every equivalent at once.
The reference values worth memorising are few: 1 kW = 1,000 W, 1 hp = 745.7 W, 1 PS = 735.5 W, 1 kW = 3,412 BTU/h, and 0 dBm = 1 mW.
| Conversion | Multiply by | Example |
|---|---|---|
| kW → hp | 1.341 | 2.5 kW = 3.35 hp |
| hp → W | 745.7 | 5 hp = 3,728 W |
| kW → BTU/h | 3,412.14 | 3.5 kW = 11,942 BTU/h |
| PS → hp | 0.986 | 150 PS = 147.9 hp |
| W → dBm | 10 log₁₀ (W × 1,000) | 1 W = 30 dBm |
How do you convert kilowatts to horsepower without getting it wrong?
To convert kilowatts to horsepower, multiply by 1.34102209 for mechanical horsepower: 1 kW = 1.341 hp, 2.5 kW = 3.353 hp, 10 kW = 13.41 hp. Divide by the same factor to go back — unless the source figure is metric PS, in which case multiply by 1.35962.
This matters most when comparing engines: a German datasheet quoting 150 PS and an American one quoting 150 hp describe engines about 2 hp apart, and across a fleet that gap compounds into real differences in fuel and load.
Always check whether a horsepower figure is mechanical hp or metric PS before converting. European car and machinery specs usually quote PS; US specs usually quote hp. The 1.4% gap between them is small on one engine and significant across a fleet.
A worked example: sizing a generator for a small workshop
Consider a fictional but realistic scenario. Sara runs a small woodworking workshop outside Lahore with three machines she sometimes runs together: a table saw rated at 2.2 kW, a dust extractor rated at 1.5 hp, and an air compressor with a 2 hp motor.
Here is the conversion chain, step by step:
- Table saw: already in kilowatts — 2.2 kW, no conversion needed.
- Dust extractor: 1.5 hp × 745.7 = 1,118.6 W, or about 1.12 kW.
- Air compressor motor: rated at 2 hp on its plate, which is 2 × 745.7 = 1,491 W, or about 1.49 kW.
- Total running load: 2.2 + 1.12 + 1.49 = 4.81 kW.
- Starting surge: motors typically draw 2–3 times their running power at startup, so Sara plans for roughly 12–14 kW of surge capacity rather than buying a 5 kW generator that would trip the moment two machines start together.
Running each step through a power converter takes under a minute, and the all-conversions table lets her sanity-check every figure in both directions. The alternative — a calculator, three web searches, and a guessed factor — is exactly how a workshop ends up with a generator that stalls under load.
Running watts and starting watts are different numbers. Always size a generator on starting watts for the largest motor plus running watts for everything else. A converter gives you the unit translation; it does not replace checking the motor's startup rating on its plate.
What about BTU/h, watts, and air conditioning?
BTU per hour measures heat, not electricity, which is why air conditioner conversions confuse people. A 12,000 BTU/h unit — "one ton" in HVAC language — moves 12,000 BTU of heat per hour but draws only about 3,517 watts to do it. Confusing the two overstates electrical load by more than three times.
The conversion itself is simple: multiply kW by 3,412.14 to get BTU/h, or divide BTU/h by 3,412.14 to get kW. A 2.5 kW heater produces about 8,530 BTU/h, while a 12,000 BTU/h air conditioner draws roughly 3.5 kW. When comparing heating and cooling kit, convert both figures to watts first and the comparison becomes honest.
How does dBm fit into a power converter?
dBm is power measured against a 1-milliwatt reference, calculated as 10 log₁₀(power in milliwatts). That makes it logarithmic: 0 dBm is 1 mW, 10 dBm is 10 mW, 20 dBm is 100 mW, and 30 dBm is 1 W. Every 3 dBm roughly doubles the power, and every 10 dBm multiplies it by ten.
This matters in Wi-Fi and radio work, where signal strength is quoted in dBm and transmitter output in watts. A router advertising 20 dBm transmits 100 mW; a 30 dBm access point transmits a full watt. A plain multiplication converter gives wrong answers for dBm — the tool needs its own log formula, and CodexFuse's converter handles dBm that way.
Wrong unit conversions mean undersized generators, overloaded circuits, and cooling that cannot keep up. CodexFuse's free converter gives you every equivalent instantly — and when the job grows beyond a conversion, the same fully managed platform, on credits, handles your hosting, email, security, and backups without subscriptions.
Get Started with CodexFuseWhat a power converter does not do
Honest limits matter. A power converter translates units; it does not tell you whether a motor, generator, or air conditioner is right for your job. It cannot account for efficiency losses, power factor, startup surge, altitude derating, or local electrical codes.
It also cannot verify the number you typed. If a datasheet quotes horsepower but means PS, the converter will faithfully convert the wrong input. Always check the source unit against the equipment plate, and treat any conversion as one input into a sizing decision, not the decision itself.
How does this fit into a managed IT workflow?
Power conversions rarely live alone. They show up while planning infrastructure: sizing UPS units for a server room, estimating a new office's electrical load, or checking a hosting setup's power budget. That is where scattered tools become their own problem — one tab each for conversions, hosting, email, and backups, each with its own bill.
CodexFuse works the other way. The converter is free and runs in your browser with no install, and the wider platform is fully managed on credits: buy credits, use them across hosting, VPS, business email, security, and backups, with nothing renewing or locking you in. The practical workflow is simple — convert the numbers with the free power converter, size the infrastructure honestly, then run it on one managed platform instead of five vendors.
For teams that convert files as often as units, the same free toolbox covers that too — converting spreadsheets with an Excel to JSON converter, generating secure tokens with a random string generator, or checking search visibility with a noindex checker. One account, one credit balance, no subscription sprawl.
If you work with file conversions as well as unit conversions, see how to convert MP3 to AAC for smaller, efficient audio, or blend two images together with the free image merger.
Frequently Asked Questions
How do I convert kW to hp?
Multiply kilowatts by 1.34102209 for mechanical horsepower: 1 kW = 1.341 hp, 2.5 kW = 3.353 hp. Divide by the same factor to go back, and use 1.35962 if your figure is metric PS.
How many watts is 5 horsepower?
5 hp = 3,728.5 W, since 1 hp = 745.7 W. The same factor gives 1 MW = 1,341 hp and 1 hp = 2,544.4 BTU/h. If the figure is metric PS, 5 PS = 3,677.5 W.
How do I convert kW to BTU per hour?
Multiply kW by 3,412.141633: 1 kW = 3,412.14 BTU/h, 3.5 kW = about 11,942 BTU/h. Going the other way, 12,000 BTU/h = 3,517 W — what HVAC installers call one ton of refrigeration.
What is the difference between hp and PS?
Mechanical hp is 745.69987158227 W; metric PS is 735.49875 W, about 1.4% smaller. So 150 PS = about 147.9 hp. European specs usually quote PS, US specs hp — confirm which one a figure uses before comparing.
What is dBm and why is it different?
dBm is power against a 1-milliwatt reference: dBm = 10 log₁₀(power in mW). So 0 dBm = 1 mW, 30 dBm = 1 W, 10 W = 40 dBm. Because the scale is logarithmic, dBm needs its own formula, not a plain multiplication factor.
Is the CodexFuse power converter really free?
Yes. It runs in your browser with no install, shows all ten unit equivalents for any input at once, and copies the result with one click. Results use 10 significant figures, with scientific notation for very large or tiny values.
Convert it right, then build on a platform that stays simple
Every wrong unit conversion is a small decision made with bad numbers — a generator that stalls, a cooling system that falls short, an engine comparison that misleads. A free power converter removes that risk in under a minute.
But conversions are only the start of the infrastructure decisions behind them. If you are sizing real systems — servers, offices, workshops, or a growing business's entire IT setup — stop paying five vendors on five subscriptions to babysit it all. Move your hosting, business email, security, and backups to CodexFuse today: one fully managed platform, pay-as-you-go credits, no lock-in. Get started with CodexFuse now and put the subscription chaos behind you.
