Compound Unit Converter
Type any unit expression — kg·m/s², BTU/(h·ft²·°F), N·m, lbf/in² — and convert it, or see its SI form and name.
Result
5.678263341 W/(m²·K)
- Factor
- 1 BTU/(h·ft²·°F) = 5.678263341 W/(m²·K)
- Target read as
- W / (m²·K)
- Read as
- BTU / (h·ft²·degF)
- In SI base units
- 5.678263341 kg·s⁻³·K⁻¹
- Quantity
- heat transfer coefficient (U-value) (mass ÷ time³ × temperature)
Temperatures inside a compound unit are differences (1 °F step = 5/9 K); a lone °F or °C converts as a temperature scale.
Show the work
Multiply by the unit's size in SI base units
1 BTU/(h·ft²·°F) = 5.678263341 kg·s⁻³·K⁻¹, and 1 W/(m²·K) = 1 kg·s⁻³·K⁻¹
1 × 5.678263341 = 5.678263341 W/(m²·K)
How it works
Each unit is reduced to SI base units (kg, m, s, A, K, cd, mol) with mathjs; two units convert only when their dimensions match, and the factor is the ratio of their SI values.
Write units with · * or spaces for multiply, / for divide and ^2 or ² for powers. Temperatures inside a compound unit (like °F in BTU/(h·ft²·°F)) are temperature differences: 1 °F step = 5/9 K. BTU is the International Table BTU (1055.05585262 J). mathjs is Apache-2.0 licensed.
Questions
- How does the compound unit converter work?
- Each unit is reduced to SI base units (kg, m, s, A, K, cd, mol) with mathjs; two units convert only when their dimensions match, and the factor is the ratio of their SI values.
- What does it assume?
- Write units with · * or spaces for multiply, / for divide and ^2 or ² for powers. Temperatures inside a compound unit (like °F in BTU/(h·ft²·°F)) are temperature differences: 1 °F step = 5/9 K. BTU is the International Table BTU (1055.05585262 J). mathjs is Apache-2.0 licensed.
- Why does it say the units don't match?
- Only quantities of the same kind convert — a force (N) can't become a power (W). The message lists both dimensions so you can spot a missing or extra unit.
- Can I leave the target blank?
- Yes. It then shows the value in SI base units and, when one fits, the named SI unit (for example kg·m/s² = N).
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