100°F in Celsius

100 degrees Fahrenheit =
37.78°C

📐 Calculation

Formula: °C = (°F - 32) × 5/9

(100 - 32) × 5/9
= 68 × 0.5556
= 37.78°C

What does 100°F feel like?

100 degrees Fahrenheit (37.78°C) is remarkably close to normal human body temperature, which averages 37°C (98.6°F). At this temperature, the air would feel extremely warm, similar to a very hot summer day or a fever.

Understanding 100°F in Context

In the UK, temperatures rarely reach 100°F. The highest temperature ever recorded in Britain was 40.3°C (104.5°F) in Coningsby, Lincolnshire, on 19 July 2022. When temperatures approach 100°F in the UK, it's considered a heatwave emergency.

Health Considerations at 100°F

When air temperature reaches 100°F (37.78°C), your body struggles to cool itself through sweating. The NHS recommends:

100°F in Cooking

In cooking, 100°F is an important temperature for bread making. This is the ideal temperature for activating yeast - warm enough to encourage growth but not hot enough to kill the yeast organisms. Professional bakers often use water at exactly 100-110°F (37-43°C) for their dough.

Body Temperature Context

If your body temperature reaches 100°F (37.78°C), you're running a slight fever. Normal body temperature ranges from 36.1°C to 37.2°C (97°F to 99°F). A temperature above 38°C (100.4°F) is generally considered a fever that may require medical attention.

Why Use Fahrenheit in the UK?

While the UK officially uses Celsius, many older British residents still think in Fahrenheit, especially for weather. Understanding both scales is useful when reading American recipes, weather forecasts, or communicating with people from the US.

Related Conversions

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