What temperature is the same in both Fahrenheit and Celsius?

-40 degrees is the same in both scales. This is the only point where Fahrenheit and Celsius intersect.

What is normal body temperature in Fahrenheit and Celsius?

Normal body temperature is 98.6°F (37°C), though individual normal ranges vary from about 97°F to 99°F (36.1°C to 37.2°C). A fever is generally considered 100.4°F (38°C) or higher.

Why does the US use Fahrenheit?

Daniel Fahrenheit's scale was widely adopted in English-speaking countries in the 1700s. When most of the world switched to Celsius in the mid-20th century, the US chose not to mandate the change, though Celsius is used in US science and medicine.

What's the fastest way to estimate Celsius to Fahrenheit?

Double the Celsius number and add 30. It's not exact but works well for everyday temperatures. Example: 20°C → (20×2)+30 = 70°F (actual: 68°F). Close enough for deciding what to wear.

Fahrenheit vs Celsius — Quick Conversions and When Temperature Matters

Is 25°C warm enough for shorts? Is 180°C the right oven temperature for chicken? What does it mean when the weather app abroad says “it feels like -5”?

If you’ve ever traveled internationally or followed a recipe from another country, you’ve hit the Fahrenheit-Celsius wall. Here’s how to break through it.

The Conversion Formulas

Fahrenheit to Celsius: (°F - 32) × 5/9 = °C. So 72°F: (72-32) × 5/9 = 40 × 0.556 = 22.2°C.

Celsius to Fahrenheit: (°C × 9/5) + 32 = °F. So 25°C: (25 × 1.8) + 32 = 45 + 32 = 77°F.

Those formulas are precise but hard to do in your head. Use these shortcuts instead.

The Quick Estimation Trick

Celsius to Fahrenheit: Double it and add 30. This gives you a surprisingly close estimate for everyday temperatures. 10°C → 50°F (exact: 50°F, perfect). 20°C → 70°F (exact: 68°F). 30°C → 90°F (exact: 86°F). 35°C → 100°F (exact: 95°F).

Fahrenheit to Celsius: Subtract 30, then halve it. 70°F → 20°C (exact: 21.1°C). 90°F → 30°C (exact: 32.2°C). It gets less accurate at extremes, but for weather temperatures it works great.

Weather Reference Points

Here’s what common Celsius temperatures feel like in Fahrenheit terms:

-10°C (14°F) is bitterly cold — heavy winter coat, gloves, hat mandatory. 0°C (32°F) is freezing — literally, water turns to ice. 10°C (50°F) is cool — light jacket weather. 20°C (68°F) is comfortable room temperature. 25°C (77°F) is warm and pleasant. 30°C (86°F) is hot — summer day. 35°C (95°F) is very hot — stay hydrated. 40°C (104°F) is dangerously hot — heat advisory territory.

Cooking Temperatures

Oven temperatures are where Fahrenheit-Celsius confusion causes the most practical problems.

150°C = 300°F (low/slow cooking). 180°C = 350°F (standard baking — cookies, cakes). 200°C = 400°F (roasting vegetables, chicken). 220°C = 425°F (high-heat roasting, pizza). 230°C = 450°F (bread, high-heat searing).

For meat doneness: Rare beef is 125°F (52°C). Medium is 145°F (63°C). Well-done is 160°F (71°C). Chicken must reach 165°F (74°C) for food safety.

Medical Temperatures

Normal body temperature: 98.6°F (37°C). Low-grade fever: 99-100.3°F (37.2-37.9°C). Fever: 100.4°F+ (38°C+). High fever requiring medical attention: 103°F+ (39.4°C+). Hypothermia: below 95°F (35°C).

For children, always consult a pediatrician for fevers over 100.4°F (38°C) in infants under 3 months.

Convert Instantly

Skip the mental math and use our free Temperature Converter for instant, precise conversions between Fahrenheit, Celsius, and Kelvin.