# Thermal Resistance Converter (K/W / °C/W / °F·h/BTU)

Convert thermal resistance between K/W (kelvin per watt, SI base), °C/W (1 = 1 K/W, since Δ1 K = Δ1 °C exactly), and °F·h/BTU International Table (1 = 1.8956342 K/W). Converts via K/W to the target unit and lists the equivalent value in all three units for reference. Reference values: CPU heatsink ≈ 0.1–0.3, LED thermal path ≈ 5–20, natural convection ≈ 1 K/W.

> Canonical page: https://elysiatools.com/en/tools/thermal-resistance-converter

- **Category:** Math & Numbers

- **Keywords:** thermal resistance, thermal resistance conversion, K/W, kelvin per watt, °C/W, celsius per watt, °F·h/BTU, degree Fahrenheit hour per BTU, R-value, thermal impedance, heat sink

## Overview

Convert non-negative thermal resistance values between K/W, °C/W, and °F·h/BTU (IT). Enter a value, choose the input and output units, set decimal places from 0 to 10, and view the converted result with equivalent values in all three units.

## Inputs

- **Input unit** (select)
- **Value** (number): Thermal resistance in the selected Input unit. Must be non-negative.
- **Output unit** (select)
- **Decimal Places** (number)

## When to use

- Convert heat sink or thermal path values between SI and Imperial thermal resistance units.
- Compare thermal resistance specifications reported in K/W, °C/W, or °F·h/BTU (IT).
- Check reference values for CPU heatsinks, LED thermal paths, or natural convection.

## How it works

- Enter a non-negative thermal resistance value.
- Select the input unit: K/W, °C/W, or °F·h/BTU (IT).
- Choose the output unit and specify the number of decimal places from 0 to 10.
- The converter calculates through K/W and returns the selected conversion plus equivalent values in all three units.

## Use cases

- Heat sink specification checks for CPU cooling designs.
- LED thermal path comparisons across engineering documents.
- Thermal resistance calculations involving natural convection reference values.

## Frequently asked questions

### Which thermal resistance units are supported?

The converter supports K/W, °C/W, and °F·h/BTU (IT).

### Are K/W and °C/W equivalent?

Yes. A temperature difference of 1 K equals a temperature difference of 1 °C, so the numerical values are the same.

### How is °F·h/BTU converted to K/W?

One °F·h/BTU (IT) equals 1.8956342 K/W.

### Can I enter a negative value?

No. The thermal resistance value must be non-negative.

### How many decimal places can the result use?

You can set the result to between 0 and 10 decimal places.

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