Temperature Converter
Convert temperatures between Celsius, Fahrenheit, and Kelvin.
Free Online Temperature Converter
Converting temperatures accurately is a daily necessity. Whether you are an Indian home chef following an international baking recipe, a traveler checking weather updates abroad, or a student solving physics problems, getting the temperature right is critical.
Unlike measuring distance or weight (which simply scale up from zero), temperature systems have entirely different starting points—like the freezing point of water or absolute zero. Because of this, you must use specific mathematical formulas that combine multiplication, division, addition, and subtraction to convert accurately. Doing this manually can easily lead to errors.
Our free online Temperature Converter does the math for you instantly. Designed for quick, accurate conversions, it helps users switch effortlessly between Celsius (°C), Fahrenheit (°F), and scientific Kelvin (K).
How to Use the Temperature Calculator
Our tool is designed for absolute simplicity. Convert between any major temperature scales in just three easy steps:
Step 1: Enter the Temperature
- Locate the main Temperature input box on the screen.
- Type the numerical value you want to convert (for example, type "12").
- Our calculator accepts positive numbers, negative numbers (e.g., -40), and decimals (e.g., 98.6).
Step 2: Select Your Units
- Click the From Unit dropdown menu to choose your starting measurement.
- Click the To Unit dropdown menu to pick the scale you want to convert into.
- Available Options:
- Celsius (°C)
- Fahrenheit (°F)
- Kelvin (K)
Step 3: View the Result
The calculator works instantly as you type or change units. Look at the large green output panel on the right side of your screen to see the final conversion (e.g., entering 12 Celsius to Fahrenheit will instantly show 53.6 Fahrenheit).
Temperature Conversion Formulas
If you are a student preparing for exams or simply curious about the math behind the magic, here are the exact formulas used to calculate temperature conversions.
1. Celsius & Fahrenheit Formulas
These are the two most commonly used temperature scales globally. While India relies on Celsius (°C) for weather, the US uses Fahrenheit (°F).
- Celsius to Fahrenheit (°C to °F): Multiply the temperature by 1.8 (or 9/5), then add 32.
Formula: (°C × 1.8) + 32 = °F - Fahrenheit to Celsius (°F to °C): Subtract 32, then divide by 1.8 (or multiply by 5/9).
Formula: (°F - 32) × 5/9 = °C
2. Kelvin Formulas (Scientific)
Kelvin (K) is the absolute temperature scale used primarily in scientific research, engineering, and astronomy. 0 K represents "Absolute Zero"—the theoretical point where all molecular movement stops.
- Celsius to Kelvin: Because one degree Celsius is the exact same size as one Kelvin, you only need to add an offset.
Formula: °C + 273.15 = K - Kelvin to Celsius: Subtract the offset.
Formula: K - 273.15 = °C - Fahrenheit to Kelvin: Convert to Celsius first in the middle of the equation, then to Kelvin.
Formula: (°F - 32) × 5/9 + 273.15 = K
Real-Life Conversion Examples
Let's look at a few practical, everyday scenarios to see how these temperature conversions play out in the real world.
Example 1: Checking for a Fever (Fahrenheit to Celsius)
In India, doctors and digital thermometers still predominantly use Fahrenheit to measure body temperature. A thermometer reads 101°F. How much is this in Celsius?
- Starting Value: 101°F
- Formula used: (°F - 32) × 5/9 = °C
- Calculation: (101 - 32) = 69. Next, 69 × (5 ÷ 9)
- Final Answer: 38.33°C (This indicates a fever, as normal human body temperature is around 37°C).
Example 2: Baking an American Cake (Fahrenheit to Celsius)
You find a great cake recipe online, but the instructions are from the US and say to preheat your oven to 350°F. Your oven at home only has Celsius settings.
- Starting Value: 350°F
- Formula used: (°F - 32) ÷ 1.8 = °C
- Calculation: (350 - 32) = 318. Next, 318 ÷ 1.8
- Final Answer: 176.6°C (You can safely set your oven to 175°C or 180°C).
Example 3: Science Class Data (Celsius to Kelvin)
Your physics teacher asks you to convert a standard room temperature of 25°C into Kelvin for an experiment worksheet.
- Starting Value: 25°C
- Formula used: °C + 273.15 = K
- Calculation: 25 + 273.15
- Final Answer: 298.15 K.
Frequently Asked Questions (FAQs)
What is normal human body temperature?
At what temperature does water boil and freeze?
Is there a temperature where Celsius and Fahrenheit are the same?
Which temperature scale is used in India?
Why doesn't Kelvin use the degree (°) symbol?
What is Absolute Zero?
Explore Related Scientific & Math Calculators
Need to calculate other metrics? Check out our suite of free online conversion tools: