About the Temperature Converter

Temperature is measured differently around the world. The United States primarily uses Fahrenheit, while most other countries use Celsius. Scientists worldwide use Kelvin. Our temperature converter handles all three scales instantly, with formulas and reference points to help you understand the relationships between them.

Conversion options:

Celsius ↔ Fahrenheit
Celsius ↔ Kelvin
Fahrenheit ↔ Kelvin

Temperature Conversion Formulas

Celsius to Fahrenheit

°F = (°C × 9/5) + 32

Example: Convert 25°C to Fahrenheit °F = (25 × 9/5) + 32 = 45 + 32 = 77°F

Fahrenheit to Celsius

°C = (°F - 32) × 5/9

Example: Convert 98.6°F to Celsius °C = (98.6 - 32) × 5/9 = 66.6 × 5/9 = 37°C

Celsius to Kelvin

K = °C + 273.15

Example: Convert 20°C to Kelvin K = 20 + 273.15 = 293.15 K

Kelvin to Celsius

°C = K - 273.15

Fahrenheit to Kelvin

K = (°F - 32) × 5/9 + 273.15

Quick Mental Conversion Trick (C to F)

Double the Celsius temperature, add 30:

10°C → 20 + 30 = ~50°F (actual: 50°F ✓)
20°C → 40 + 30 = ~70°F (actual: 68°F ≈)
30°C → 60 + 30 = ~90°F (actual: 86°F ≈)

For more precision, double, add 30, then add 2 for every 10°C.

Common Temperature Reference Points

Description	Celsius	Fahrenheit	Kelvin
Absolute zero	-273.15°C	-459.67°F	0 K
Freezing point of water	0°C	32°F	273.15 K
Room temperature	20-22°C	68-72°F	293-295 K
Body temperature	37°C	98.6°F	310.15 K
Boiling point of water	100°C	212°F	373.15 K
Comfortable beach day	27°C	80°F	300 K
Hot summer day	35°C	95°F	308 K
Bread baking	180°C	356°F	453 K
Pizza oven	260°C	500°F	533 K
Lead melts	327°C	621°F	600 K
Iron melts	1,538°C	2,800°F	1,811 K
Surface of the Sun	5,500°C	9,932°F	5,773 K

Cooking Temperatures

Food	Celsius	Fahrenheit	Notes
Rare steak	52°C	125°F	Internal temp
Medium steak	60°C	140°F	Internal temp
Well-done steak	71°C	160°F	Internal temp
Chicken (safe)	74°C	165°F	Internal temp
Pork (safe)	71°C	160°F	Internal temp
Baked goods	175-190°C	350-375°F	Oven temp
Roast vegetables	200°C	400°F	Oven temp
Deep frying	175-190°C	350-375°F	Oil temp
Candy (soft ball)	112°C	234°F	Sugar syrup
Candy (hard crack)	149°C	300°F	Sugar syrup

Weather Benchmarks

Description	Celsius	Fahrenheit
Freezing	0°C	32°F
Cold (jacket needed)	5-10°C	40-50°F
Cool (light jacket)	10-15°C	50-60°F
Mild (comfortable)	15-20°C	60-68°F
Warm (pleasant)	20-25°C	68-77°F
Hot (uncomfortable)	30°C+	86°F+
Dangerous heat	40°C+	104°F+

The Three Temperature Scales Explained

Celsius (°C)

Developed by: Anders Celsius (1742)
Basis: Water freezes at 0°, boils at 100°
Used in: Most countries, science, medicine
Advantage: Intuitive, metric-aligned

Fahrenheit (°F)

Developed by: Daniel Gabriel Fahrenheit (1724)
Basis: Brine freezes at 0°, human body at ~96° (originally)
Used in: United States, Belize, Cayman Islands, Bahamas
Advantage: More granular for weather (1.8× more degrees between freezing and boiling)

Kelvin (K)

Developed by: Lord Kelvin (1848)
Basis: Absolute thermodynamic scale; 0 K = absolute zero
Used in: Science, physics, chemistry, astronomy
Advantage: No negative values; directly proportional to molecular energy

Frequently Asked Questions

Why does the U.S. still use Fahrenheit?

Historical inertia and the cost of converting infrastructure. Fahrenheit provides slightly more precision for weather reporting since the scale has 180 degrees between freezing and boiling vs. 100 in Celsius.

At what temperature are Celsius and Fahrenheit equal?

-40° is the same in both scales. °C = °F at -40.

Is Kelvin ever used outside science?

Rarely in daily life, but color temperature of light bulbs is measured in Kelvin (e.g., 2700K warm white, 5000K daylight).

How do I convert oven temperatures?

Use the calculator above or memorize: 180°C = 350°F (the most common baking temperature). From there, every 10°C ≈ 25°F.

What is absolute zero?

The theoretical temperature at which all molecular motion stops: -273.15°C, -459.67°F, or 0 K. It has never been fully achieved in a lab.

Temperature Converter