Celsius (°C) - Unit Information & Conversion

Definition

Degree Celsius (°C) is a unit of temperature on the Celsius scale, a temperature scale named after the Swedish astronomer Anders Celsius. It is one of the most common temperature scales used worldwide, particularly in science and in most countries for everyday measurements. The scale defines 0°C as the freezing point of water and 100°C as the boiling point of water at standard atmospheric pressure.

History

The Celsius scale was developed by Anders Celsius in 1742. Originally, he proposed a scale where 0° represented the boiling point of water and 100° represented the freezing point. This scale was later inverted by Carl Linnaeus or Jean-Pierre Christin to the form we use today. The degree Celsius was adopted as part of the International System of Units (SI), where it is defined relative to the Kelvin scale (0°C = 273.15 K).

Common Uses

• Weather: Everyday weather reporting and forecasting in most parts of the world.
• Domestic: Domestic temperature settings (thermostats, ovens).
• Science: Scientific research, especially in chemistry and biology, alongside Kelvin.
• Medical: Medical temperature measurements.
• Culinary: Food storage and cooking temperatures.

Unit FAQs

Is Celsius the same as Centigrade?

Yes, 'Celsius' and 'Centigrade' refer to the same temperature scale. The name was officially changed to Celsius in 1948 to honor Anders Celsius and avoid confusion with 'centigrade' as an angular unit.

How does Celsius relate to Kelvin?

The Celsius scale is defined relative to the Kelvin scale, the SI base unit for temperature. A temperature difference of 1°C is equal to a difference of 1 K. To convert Celsius to Kelvin, add 273.15 (K = °C + 273.15).

Why is Celsius used so widely?

Its definition based on the freezing and boiling points of water at standard pressure makes it intuitive for everyday life and many scientific applications. It provides a convenient reference range for common environmental temperatures.