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Temperature Converter

Quickly convert temperatures between Celsius, Fahrenheit, and Kelvin while seeing all three scales at once.

Inputs

Enter the temperature you know and choose both the starting and target scales.

Your details

Numeric value to convert

Scale the temperature is currently expressed in.

Scale you want the converted value in.

Results update instantly

Results

Example using default values

Converted temperature and all scale equivalents

Converted temperature
68

Temperature expressed in the target scale you selected.

Estimate, not a legal decision

Read methodology

Use the result as decision support and planning help. For high-stakes choices, confirm the details with the relevant authority, lender, employer, or adviser.

Result details

Celsius
20

Equivalent value in degrees Celsius.

Fahrenheit
68

Equivalent value in degrees Fahrenheit.

Kelvin
293.15

Equivalent value in Kelvin.

Analysis & guidance

  • Compare weather quickly

    Planning a trip? Convert the forecast to your preferred scale and keep the reference values handy.

  • Science-friendly

    Always see Kelvin alongside Celsius and Fahrenheit so lab work and homework stay consistent.

  • Cooking or brewing

    Many recipes list temperatures in different systems—convert once and keep the cross-reference nearby.

About this calculator

Temperature conversion: Celsius, Fahrenheit, Kelvin

Temperature scales measure the same physical concept, but they use different zero points and step sizes.

The three common scales

  • Celsius (°C): water freezes at 0°C and boils at 100°C (at normal atmospheric pressure).
  • Fahrenheit (°F): water freezes at 32°F and boils at 212°F.
  • Kelvin (K): an absolute scale used in science. 0 K is absolute zero.

Quick conversion formulas

  • F = C * 9/5 + 32
  • C = (F - 32) * 5/9
  • K = C + 273.15

Common questions

  • Why is 32°F equal to 0°C? Fahrenheit uses a different reference point.
  • Can Kelvin be negative? No. Kelvin starts at absolute zero.

How to use the converter

  1. Choose the input scale.
  2. Enter the temperature value.
  3. Read the converted values in the other scales.

If you’re converting for cooking or weather, rounding to one decimal is usually enough. For scientific work, keep more decimals.

How the calculation works

Simple inputs

Pick the scale you know, enter the temperature, and choose the scale you need. The converter keeps everything in sync behind the scenes.

Always see every scale

Even when you target a single scale, the calculator shows Celsius, Fahrenheit, and Kelvin equivalents so you can compare or reuse the number instantly.

Perfect for science and travel

Use it for lab work, cooking, travel planning, or weather comparisons—any time you need to jump between temperature systems.

Frequently asked questions

What’s the difference between Celsius, Fahrenheit, and Kelvin?

Celsius and Fahrenheit are common everyday scales, while Kelvin is an absolute scale used in science. Kelvin starts at absolute zero and has no negative values in physical reality.

Can Kelvin be negative?

No. 0 K is absolute zero, the theoretical lowest temperature. If you enter values that would imply negative Kelvin, double-check the input or scale.

What formulas are used for conversion?

Common formulas are: `F = C * 9/5 + 32`, `C = (F - 32) * 5/9`, and `K = C + 273.15`. The converter applies these consistently.

Why is 32°F equal to 0°C?

Fahrenheit uses a different zero point and degree size. The 32°F offset is part of how the scale was originally defined.

How to read this calculator

These results are meant as guidance. They are based on rules, assumptions, and simplified models that can differ from your exact real-world situation.

Estimate, not a legal decision

Use the result as decision support and planning help. For high-stakes choices, confirm the details with the relevant authority, lender, employer, or adviser.

Methodology

Each calculator uses defined inputs, assumptions, and logic. We explain the broader approach on the methodology page.

Read methodology

Sources and updates

Important calculators should be traceable back to official rules, public guidance, or other clearly stated references.

Read about sources

Continue calculating

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