Why is temperature interval conversion different from temperature conversion?

Absolute temperature conversion includes offsets (like +32 for Celsius to Fahrenheit). Temperature interval conversion is just scaling—no offset. A 10-degree rise is a 10-degree rise, regardless of starting temperature. You only multiply by the scale factor.

When do I use temperature interval conversion?

Use interval conversion for: temperature changes (ΔT), thermal expansion calculations, heat transfer rates, temperature differences in formulas, and any specification that says 'per degree' (like thermal conductivity W/m·K or thermal coefficient per °C).

Is 1 Kelvin the same as 1 degree Celsius?

For intervals, yes. A 1 K temperature change equals a 1°C temperature change. The scales differ only in their zero points (0 K = -273.15°C). The interval (degree size) is identical, which is why scientific formulas often use K and °C interchangeably for temperature differences.

温度间隔 Converter

About Temperature Interval Conversion

Temperature interval (or temperature difference) conversion is fundamentally distinct from absolute temperature conversion—a crucial distinction that causes frequent errors. While 0°C ≠ 0°F (they differ by 32 degrees), a change of 1°C exactly equals a change of 1.8°F. There's no offset involved in interval conversion, only scaling. This matters whenever you see "per degree" in a unit, like W/m·K or ppm/°C.

The SI unit for temperature interval is the kelvin (K), which has exactly the same size as one degree Celsius—they differ only in their zero points. Temperature intervals appear constantly in engineering: thermal expansion coefficients, heat transfer calculations, temperature rise specifications, thermocouple sensitivity, and any context involving temperature changes or differences rather than absolute temperatures.

Our converter handles temperature interval conversions correctly, applying only the scale factor without the offset that absolute temperature conversion requires.

Temperature Interval Conversions

From	To	Multiply By
ΔK	Δ°C	1 (equivalent)
ΔK	Δ°F	1.8
Δ°F	ΔK	0.5556
Δ°C	Δ°F	1.8
Δ°F	Δ°C	0.5556
ΔK	Δ°R (Rankine)	1.8
Δ°R	ΔK	0.5556
Δ°C	Δ°R	1.8
Δ°R	Δ°C	0.5556
Δ°F	Δ°R	1 (equivalent)

Temperature Interval Unit Reference

Kelvin (K) – The SI unit for temperature interval (same symbol as absolute temperature, but context determines meaning). 1 K interval exactly equals 1°C interval—they share the same degree size, differing only in zero point. All SI thermal properties use kelvin intervals: W/m·K for thermal conductivity, J/kg·K for specific heat. Scientific calculations universally use kelvin for thermodynamic consistency.

Degree Celsius (°C) – Identical interval size to kelvin, making conversion trivial. A 10°C temperature rise equals a 10 K rise exactly. Practical engineering often uses °C for familiarity while scientific work uses K. Thermal expansion coefficients are commonly expressed per °C (equivalent to per K).

Degree Fahrenheit (°F) – Smaller interval than Celsius/Kelvin by the factor 5/9. A 1°C interval = 1.8°F interval (exactly 9/5). HVAC specifications, US building codes, and American engineering practice commonly use Fahrenheit intervals. A 20°F temperature rise equals an 11.1°C (or 11.1 K) rise.

Degree Rankine (°R) – The absolute temperature scale using Fahrenheit-sized intervals. 1°R exactly equals 1°F interval. Used in US thermodynamics and some aerospace applications where absolute temperature in imperial units is needed. Rankine is to Fahrenheit as Kelvin is to Celsius.