Calculator
What the Heat Transfer Coefficient Converter does
Heat Transfer Coefficient Converter: 1 W/(m²·K) = 0.17611019 BTU/(h·ft²·°F), so multiply a watt per square metre kelvin value by 0.17611019 to get BTU per hour ft² °F, or divide to go back. Example: 1 W/(m²·K) = 0.17611019 BTU/(h·ft²·°F).
Feed it Value, From and To; it hands back Result, How it was calculated and Reverse conversion. Adjust anything and the figures re-derive on the spot.
Most people who open the Heat Transfer Coefficient Converter are students converting units for homework. Unit mistakes are quietly expensive. They have wrecked spacecraft and ruined recipes alike.
The page holds your values in memory and forgets them the moment you close it.
Below the tool you will find the field reference, the method, and an example computed from the values it opens with.
What do the Heat Transfer Coefficient Converter fields mean?
The Heat Transfer Coefficient Converter uses 3 inputs. The page opens in a usable state: real values in, real answer out, ready to edit.
| Field | What to enter | Default |
|---|---|---|
| Value | required | 1 |
| From | choose from Watt per square metre kelvin (W/(m²·K)), Kilocalorie per hour m² °C (kcal/(h·m²·°C)) or BTU per hour ft² °F (BTU/(h·ft²·°F)) | Watt per square metre kelvin (W/(m²·K)) |
| To | choose from Watt per square metre kelvin (W/(m²·K)), Kilocalorie per hour m² °C (kcal/(h·m²·°C)) or BTU per hour ft² °F (BTU/(h·ft²·°F)) | BTU per hour ft² °F (BTU/(h·ft²·°F)) |
How does the Heat Transfer Coefficient Converter work?
Both units are converted through heat transfer coefficient's base unit (W/(m²·K)), so any of the 3 units in the dropdowns can be paired in either direction without loss of accuracy.
Exact definitions are preferred throughout: the metre, the inch and the pound all have them. Only where a unit depends on a measured constant is an accepted published value substituted.
Worked example
These are the values the Heat Transfer Coefficient Converter loads by default, and the result it produces from them. Below is the same computation the tool performs on load, step by step.
| Value | 1 |
|---|---|
| From | Watt per square metre kelvin (W/(m²·K)) |
| To | BTU per hour ft² °F (BTU/(h·ft²·°F)) |
| Result | 0.17611019 BTU/(h·ft²·°F) |
|---|---|
| How it was calculated | 1 W/(m²·K) = 0.17611019 BTU/(h·ft²·°F), so 1 × 0.17611019 = 0.17611019 BTU/(h·ft²·°F) |
| Reverse conversion | 5.678263 W/(m²·K) (if you meant 1 BTU/(h·ft²·°F)) |
Heat transfer coefficient
The heat transfer coefficient measures how effectively heat moves between a solid surface and a surrounding fluid (air, water) by convection, in watts per square metre-kelvin (W/(m²·K)): a genuinely different physical process from the straight-through conduction that thermal conductivity describes.
Worth knowing
- This is a key design parameter for radiators, heat exchangers, and HVAC equipment. A higher coefficient means the surface transfers heat to (or from) the surrounding air or liquid more efficiently for a given temperature difference.
- US HVAC engineering traditionally uses BTU per hour per square foot per °F (BTU/(h·ft²·°F)) for this quantity, while most of the rest of the world uses the SI W/(m²·K) unit directly. Another instance of the imperial/metric split that runs through nearly every category on this site.
- Forced convection (a fan blowing air across a surface) produces a much higher heat transfer coefficient than natural convection (still air) for the same surface and temperature difference. The physical basis for why a fan makes a hot object feel like it’s cooling faster.
Definitions: BIPM SI Brochure · NIST reference on units
How to use it
- Type Value.
- Pick a value for From: the options are Watt per square metre kelvin (W/(m²·K)), Kilocalorie per hour m² °C (kcal/(h·m²·°C)) or BTU per hour ft² °F (BTU/(h·ft²·°F)).
- Pick a value for To: the options are Watt per square metre kelvin (W/(m²·K)), Kilocalorie per hour m² °C (kcal/(h·m²·°C)) or BTU per hour ft² °F (BTU/(h·ft²·°F)).
- The answer follows your cursor, in effect. Change a field and read the new figure.
- Look at Result, How it was calculated and Reverse conversion in the output panel.
- Copy Link when you want to return to this exact configuration; Print when someone needs it on paper.
What this tool does not do
- Factors use the internationally agreed definitions; some industries round them differently.
- Repeated conversions compound rounding, so convert once from the original value where you can.
- No allowance is made for local rules, regional variations or house conventions.
- Nothing here can catch a correct number entered in the wrong field.
Frequently asked questions
You need Value, From and To. Every box already holds a working value, so you can change one value at a time and watch how the result responds.
With the values loaded when the page opens, result comes out as 0.17611019 BTU/(h·ft²·°F). Adjust any field to see how much the answer depends on it.
No. There is no account, no session and no storage. The values exist only while the tab is open.
No charge. Everything on the page is available without signing in.
The computation is exact; how much you should trust the answer depends on how good your inputs are.