Temperature Conversion Calculator
Convert temperature from Celsius, Fahrenheit, Kelvin, Rankine or Réaumur to the corresponding temperature in any other scale.
| Temperature Scale | Value | Formula |
|---|---|---|
| Celsius (°C) | – | – |
| Fahrenheit (°F) | – | – |
| Kelvin (K) | – | – |
| Rankine (°R) | – | – |
| Réaumur (°Ré) | – | – |
Conversion Steps
Enter a temperature value and select scales to see the conversion steps.
Temperature Scale Comparison
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Temperature Conversion
Temperature Conversion helps you quickly change temperatures between different scales such as Celsius (°C), Fahrenheit (°F), Kelvin (K), Rankine (°R), and Réaumur (°Ré). Whether you’re a student, scientist, engineer, or just curious about the weather, understanding how to convert temperatures accurately makes daily life and scientific calculations much easier.
What Is Temperature Conversion?
Temperature Conversion is the process of changing a temperature value from one unit of measurement to another. For example, converting Celsius to Fahrenheit or Kelvin to Rankine. Each scale measures heat differently, so formulas are used to ensure accuracy.
If you’re working on experiments, cooking, or energy-related projects, temperature conversions are often required. Instead of memorizing all formulas, you can use the unit conversion calculator to perform quick and accurate results across multiple units — not just temperature, but also distance, area, and energy conversions.
How to Convert Celsius to Other Scales
Celsius (°C) is the most common scale worldwide. It’s based on the freezing point (0°C) and boiling point (100°C) of water.
Celsius Conversion Formulas:
- Celsius to Fahrenheit: °F = °C × 9/5 + 32
- Celsius to Kelvin: K = °C + 273.15
- Celsius to Rankine: °R = °C × 9/5 + 491.67
- Celsius to Réaumur: °Ré = °C × 4/5
Example:
Convert 50°C to Fahrenheit
°F = 50 × 9/5 + 32
°F = 90 + 32
Result: 122°F
That means 50 degrees Celsius equals 122 degrees Fahrenheit.
You can also check results instantly using the Celsius to Fahrenheit converter for error-free calculations.
Converting Fahrenheit to Other Temperature Units
The Fahrenheit (°F) scale is mainly used in the United States. It sets the freezing point of water at 32°F and the boiling point at 212°F.
Fahrenheit Conversion Formulas:
- Fahrenheit to Celsius: °C = (°F − 32) × 5/9
- Fahrenheit to Kelvin: K = (°F + 459.67) × 5/9
- Fahrenheit to Rankine: °R = °F + 459.67
- Fahrenheit to Réaumur: °Ré = (°F − 32) × 4/9
Example:
Convert 212°F to Celsius
°C = (212 − 32) × 5/9
°C = 180 × 5/9
Result: 100°C
Fahrenheit is often used in weather reports, while Celsius dominates scientific and global usage.
Kelvin Temperature Conversion
The Kelvin (K) scale is widely used in scientific research because it starts at absolute zero, the theoretical point where all molecular motion stops.
Kelvin Conversion Formulas:
- Kelvin to Celsius: °C = K − 273.15
- Kelvin to Fahrenheit: °F = K × 9/5 − 459.67
- Kelvin to Rankine: °R = K × 9/5
- Kelvin to Réaumur: °Ré = (K − 273.15) × 4/5
Example:
Convert 300 K to Celsius
°C = 300 − 273.15
Result: 26.85°C
Kelvin is essential for thermodynamics, physics, and engineering fields.
Rankine Temperature Scale
Rankine (°R) is mainly used in thermodynamics and engineering calculations within the United States. It’s similar to Kelvin but measured in Fahrenheit-sized degrees.
Rankine Conversion Formulas:
- Rankine to Celsius: °C = (°R − 491.67) × 5/9
- Rankine to Fahrenheit: °F = °R − 459.67
- Rankine to Kelvin: K = °R × 5/9
- Rankine to Réaumur: °Ré = (°R − 491.67) × 4/9
Example:
Convert 671.67°R to Kelvin
K = 671.67 × 5/9
Result: 373.15 K (Boiling point of water)
Réaumur Scale Conversion
The Réaumur (°Ré) scale, though rarely used today, was once popular in parts of Europe. It divides the freezing and boiling points of water into 80 equal parts.
Réaumur Conversion Formulas:
- Réaumur to Celsius: °C = °Ré × 5/4
- Réaumur to Fahrenheit: °F = °Ré × 9/4 + 32
- Réaumur to Kelvin: K = °Ré × 5/4 + 273.15
- Réaumur to Rankine: °R = °Ré × 9/4 + 491.67
Example:
Convert 40°Ré to Fahrenheit
°F = 40 × 9/4 + 32
°F = 90 + 32
Result: 122°F
Réaumur still finds limited use in traditional European industries, such as cheese production and sugar syrup cooking.
Temperature Conversion
Here’s a simplified temperature conversion chart for quick reference:
| Celsius (°C) | Fahrenheit (°F) | Kelvin (K) | Rankine (°R) | Réaumur (°Ré) |
|---|---|---|---|---|
| -273.15 (Absolute Zero) | -459.67 | 0.00 | 0.00 | -218.52 |
| 0 (Freezing Point) | 32 | 273.15 | 491.67 | 0 |
| 25 | 77 | 298.15 | 536.67 | 20 |
| 50 | 122 | 323.15 | 581.67 | 40 |
| 75 | 167 | 348.15 | 626.67 | 60 |
| 100 (Boiling Point) | 212 | 373.15 | 671.67 | 80 |
This table gives a quick overview of how temperature values align across the five scales.
Origins of the Temperature Scales
Understanding where each scale comes from adds context to why they exist:
- Celsius – Created by Anders Celsius, based on the properties of water.
- Fahrenheit – Designed by Daniel Gabriel Fahrenheit using saltwater freezing and body temperature as references.
- Kelvin – Proposed by Lord Kelvin, focusing on absolute zero where motion stops.
- Rankine – Developed by William John Macquorn Rankine, merging Fahrenheit’s size with Kelvin’s absolute base.
- Réaumur – Named after René-Antoine Ferchault de Réaumur, popular in 18th-century Europe.
Practical Uses of Temperature Conversion
Temperature conversions aren’t just for science — they apply in many real-world situations:
- Cooking & Baking: Recipes often use different temperature units. For culinary conversions, you can check the cooking conversion calculator to adjust heat settings precisely.
- Engineering & Energy: Converting between Rankine and Kelvin helps analyze thermodynamic efficiency and heat transfer.
- Weather Reports: Travelers may need to convert between Fahrenheit (U.S.) and Celsius (global) to understand forecasts.
Why Use an Online Temperature Conversion Calculator
Manually converting values using formulas is useful for learning, but it can be time-consuming. An online tool instantly gives accurate results between all scales.
Benefits include:
- Instant calculation of all five scales at once
- Error-free formulas with precise rounding
- Mobile-friendly and easy to use
- Integrated with other tools like energy converters for broader applications
Whether you’re converting a single degree or analyzing data across systems, a temperature conversion calculator saves time and prevents mistakes.
Temperature Conversion simplifies how we understand heat and energy across different scientific and everyday systems. From Celsius and Fahrenheit to Kelvin, Rankine, and Réaumur — each scale serves a unique purpose rooted in history and science.
Instead of memorizing every formula, you can rely on a precise online converter that ensures accuracy in every conversion. Mastering temperature conversions helps you connect weather, science, and technology — one degree at a time.