< class="breadcumb-title text-anim" data-cue="slideInUp" data-delay="300">Thermal Conductivity Converter
Professional Thermal Conductivity Converter — 20+ Units | W/m·K, BTU/h·ft·°F, cal/s·cm·°C | ASLI FORM

Thermal Conductivity Converter

Convert between Watt per meter Kelvin (W/m·K), BTU per hour foot Fahrenheit (BTU/h·ft·°F), calorie per second centimeter Celsius (cal/s·cm·°C) and 20+ thermal conductivity units used in engineering, physics, and materials science.

Conversion Formula
1 W/(m·K) = 0.577789 BTU/(h·ft·°F)

Common Thermal Conductivity Conversions

Quick reference from W/m·K
From (W/m·K)To UnitResult

Thermal Conductivity Units Reference

Thermal conductivity (k, λ, or κ) measures a material's ability to conduct heat. Different regions and industries use different units. Here are all the units supported by our converter:

W/(m·K) — SI Unit Watt per meter Kelvin. The standard SI unit used worldwide in scientific literature.
BTU/(h·ft·°F) — Imperial British Thermal Unit per hour foot Fahrenheit. Common in US and UK engineering.
cal/(s·cm·°C) — CGS Calorie per second centimeter Celsius. Used in older scientific literature.
kcal/(h·m·°C) — Metric Kilocalorie per hour meter Celsius. Common in European HVAC industry.
BTU·in/(h·ft²·°F) Used in US building insulation industry for R-value calculations.
mW/(m·K) — Milliwatt Milliwatt per meter Kelvin. Used for low-conductivity materials like insulators.
kW/(m·K) — Kilowatt Kilowatt per meter Kelvin. Used for high-conductivity materials like metals.
J/(s·m·K) — Equivalent to W/(m·K) Joule per second meter Kelvin. Dimensionally equivalent to W/(m·K).

Common Material Thermal Conductivity Values

Reference values at room temperature (20-25°C). Actual values may vary with temperature, purity, and material structure.

Applications of Thermal Conductivity

Thermal conductivity is critical in numerous engineering and scientific applications:

  • Building & Construction Insulation selection, R-value calculations, energy efficiency compliance.
  • Electronics Cooling Heat sink design, thermal interface materials, PCB thermal management.
  • Aerospace Engineering Thermal protection systems, spacecraft insulation, re-entry heat shields.
  • HVAC Systems Duct insulation, pipe insulation, heat exchanger design.
  • Materials Science Material selection, composite design, thermal barrier coatings.
  • Energy Systems Power plant design, solar thermal systems, geothermal applications.

How to Use This Converter

Our thermal conductivity converter is engineered for speed, precision, and ease of use. Follow these steps to get accurate conversions instantly.

  • Select Source Unit Choose the thermal conductivity unit you want to convert from (e.g., W/m·K).
  • Select Target Unit Choose the unit you want to convert to (e.g., BTU/h·ft·°F).
  • Enter Value Type your thermal conductivity value — the result appears instantly.
  • View Formula The exact conversion formula is displayed below for verification.
  • Swap Units Click the swap button to instantly reverse the conversion direction.
  • Reference Materials Check the material database for common thermal conductivity values.

Why Professionals Choose ASLI FORM

Built with precision engineering and premium design, our converter meets the demands of scientists, engineers, and researchers.

  • Scientific Precision Results accurate to 10 significant digits using NIST-standard conversion factors.
  • Instant Results Real-time conversion as you type — no buttons to click, no waiting.
  • Works Offline All calculations run locally in your browser. Perfect for field work.
  • Universal Compatibility From basic keypad phones to 4K displays — works on every device.
  • Zero Tracking No cookies, no analytics, no data collection. Your privacy is absolute.
  • Free Forever No subscriptions, no hidden fees, no usage limits, no advertisements.

Frequently Asked Questions

Thermal conductivity (denoted by k, λ, or κ) is a material property that quantifies its ability to conduct heat. It is defined as the rate at which heat energy is transferred through a material per unit cross-section area and per unit temperature gradient. The SI unit is Watt per meter Kelvin (W/m·K). Thermal conductivity is measured using methods such as the Steady-State Method, Transient Hot Wire Method, Laser Flash Analysis, and Guarded Hot Plate Method.
The SI unit of thermal conductivity is Watt per meter Kelvin (W/m·K), which can also be written as W/(m·K) or J/(s·m·K). It represents the amount of heat (in watts) that flows through a 1-meter thick material with a cross-sectional area of 1 square meter when there is a temperature difference of 1 Kelvin across it.
To convert from W/m·K to BTU/h·ft·°F, multiply by 0.577789. For example:
  • 1 W/m·K = 0.577789 BTU/h·ft·°F
  • 10 W/m·K = 5.77789 BTU/h·ft·°F
  • 100 W/m·K = 57.7789 BTU/h·ft·°F
Our converter handles this automatically with scientific precision.
Materials with the highest thermal conductivity at room temperature:
  • Graphene: ~3000-5000 W/m·K
  • Diamond: ~1000-2200 W/m·K
  • Silver: ~429 W/m·K
  • Copper: ~401 W/m·K
  • Gold: ~318 W/m·K
  • Aluminum: ~237 W/m·K
These materials are used in heat sinks, thermal management, and high-performance applications.
Materials with the lowest thermal conductivity (best insulators):
  • Aerogel: ~0.013-0.020 W/m·K
  • Vacuum: ~0 W/m·K (perfect insulator)
  • Polyurethane foam: ~0.020-0.030 W/m·K
  • Polystyrene foam: ~0.033-0.038 W/m·K
  • Fiberglass: ~0.040 W/m·K
  • Air (still): ~0.026 W/m·K
These are used in building insulation, cryogenics, and thermal protection.
Thermal conductivity (k) is a material property that measures how well a material conducts heat. Thermal resistance (R) is a measure of a material's opposition to heat flow and depends on both the material's conductivity and its thickness. The relationship is: R = L/k, where L is thickness. High conductivity means low resistance, and vice versa.
Thermal conductivity varies with temperature:
  • Metals: Generally decrease with increasing temperature
  • Insulators: Generally increase with increasing temperature
  • Gases: Increase with increasing temperature
  • Liquids: Varies by substance
For precise engineering calculations, temperature-dependent values should be used.
Yes, the ASLI FORM Thermal Conductivity Converter is 100% free forever. There are no registration requirements, no usage limits, no subscription fees, and no hidden charges. We do not display advertisements and we do not collect any personal data.
Yes. Once the page loads, all calculations happen locally in your browser. There is no server-side processing, no API calls, and no internet dependency for conversions. This makes the tool perfect for field work, laboratories, and remote locations.
Fourier's Law states that the rate of heat transfer through a material is proportional to the negative gradient of temperature and the area through which the heat flows: q = -k × ∇T, where q is heat flux, k is thermal conductivity, and T is temperature gradient. This is the fundamental equation governing heat conduction.
Absolutely. Our converter is designed with a mobile-first responsive approach and works perfectly on every device — from basic keypad phones to 4K desktop displays. The interface adapts intelligently: desktops get a sidebar, tablets get a collapsible sidebar, and mobile devices get optimized dropdowns.
We welcome feedback from our users. You can reach our support team through:
  • Phone: +91-7011993433 (Mon-Sat, 9 AM to 7 PM IST)
  • WhatsApp: Same number with pre-filled message
  • Email: support@asliform.in
Our team reviews every piece of feedback and incorporates improvements regularly.

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