How to convert Celsius to Fahrenheit?

Celsius to Fahrenheit: °F = (°C × 9/5) + 32. Example: 100°C = (100 × 9/5) + 32 = 212°F.

What is absolute zero in Celsius?

Absolute zero is −273.15°C (0 Kelvin), the theoretical lowest possible temperature where all molecular motion stops.

What temperature is the same in Celsius and Fahrenheit?

−40° is the same in both Celsius and Fahrenheit. That is, −40°C = −40°F.

Temperature Converter - Celsius, Fahrenheit, Kelvin

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Temperature Converter

Type in any field — all scales update instantly

Common reference points:

Celsius?Used in most countries worldwide. Water freezes at 0°C and boils at 100°C at sea level. °C

°C

Fahrenheit?Used primarily in the USA. Water freezes at 32°F and boils at 212°F. Body temperature is 98.6°F. °F

°F

Kelvin?The SI unit of temperature. Starts at absolute zero (0 K = −273.15°C). Used in science and engineering. No degree symbol — just K. K

Rankine?Like Kelvin but uses Fahrenheit-sized degrees. Used in some US engineering applications. 0°R = absolute zero. °R

°R

Temperature Scales Explained

There are four main temperature scales used around the world today. Celsius (°C) is used in almost every country for everyday temperature. Fahrenheit (°F) is primarily used in the United States. Kelvin (K) is the scientific standard used in physics and chemistry. Rankine (°R) is occasionally used in US engineering.

Conversion Formulas

Celsius → Fahrenheit: °F = (°C × 9/5) + 32
Fahrenheit → Celsius: °C = (°F − 32) × 5/9
Celsius → Kelvin: K = °C + 273.15
Kelvin → Celsius: °C = K − 273.15
Celsius → Rankine: °R = (°C + 273.15) × 9/5

📘 Example Scenarios

Scenario 1 — Vikram checks the weather in New York 🗽

Vikram is visiting New York and the forecast says 72°F. He's used to Celsius. He types 72 in the Fahrenheit field and sees 22.2°C — a warm, pleasant day. He packs light clothes.

Scenario 2 — Anna follows a recipe in an American cookbook 🍰

Anna's oven is in Celsius but the recipe says 350°F. She types 350 in Fahrenheit and sees 176.7°C. She sets her oven to 175°C (the nearest marker) and bakes successfully.

Key Temperature Reference Points

Some temperatures worth memorising: Water freezes at 0°C / 32°F. Water boils at 100°C / 212°F. Normal body temperature is 37°C / 98.6°F. Room temperature is typically 20–22°C / 68–72°F. The coldest recorded temperature on Earth was −89.2°C / −128.6°F (Antarctica, 1983).

Frequently asked questions

Multiply by 9/5 then add 32: °F = (°C × 1.8) + 32. Quick mental trick: double the Celsius, subtract 10%, then add 32. For 20°C: 20×2=40, minus 10%=36, plus 32=68°F (accurate: 68°F).

The USA adopted Fahrenheit in the early 1700s and it became deeply embedded in the culture and infrastructure. Unlike most countries that metricated in the 20th century, the US largely retained its traditional measurement systems.

Absolute zero (0 K = −273.15°C = −459.67°F) is the lowest theoretically possible temperature. At absolute zero, all molecular motion ceases. It has never been fully achieved but scientists have come within billionths of a degree.

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