Temperature Converter
Easify your degrees — convert between Celsius, Fahrenheit, and Kelvin.
Convert temperatures between Celsius, Fahrenheit, Kelvin, and Rankine instantly. Perfect for cooking, science, and travel.
Temperature Milestones
Click any milestone to load that temperature. Your position is marked on the timeline.
Body Temperature / Fever Check
Cooking Temperature Guide
Click any temperature to load it in the converter.
Conversion Formulas
Quick Mental Math Tricks
Great for travelers! No calculator needed.
Quick Popular Conversions
Click any to instantly convert.
How to Use
Temperature conversion is one of the most common daily calculations worldwide, whether you're a traveler checking weather in a different country, a cook following a recipe from another region, a student studying thermodynamics, or a parent checking a child's fever. This tool converts between all five major temperature scales instantly.
The Five Scales
Celsius (Anders Celsius, 1742) is used worldwide and based on water's freezing (0°) and boiling (100°) points. Fahrenheit (Daniel Fahrenheit, 1724) is used in the US and based on an older brine/body-temperature calibration. Kelvin (Lord Kelvin) starts at absolute zero and is the SI unit for science. Rankine is Kelvin's Fahrenheit equivalent, used in some engineering fields. Réaumur is a historic European scale still occasionally referenced.
The Immersive Experience
What makes this converter unique is the immersive background that shifts with temperature — icy blue with falling snowflakes at sub-zero, warm yellow with sun rays at 25°C, scorching red with heat waves at 40°C+, and volcanic embers above 100°C. The animated SVG thermometer with dual-scale markings and color-shifting mercury makes conversion visual and intuitive. Glass morphism cards let the background tint show through, so you literally feel the temperature through your screen.
Beyond Basic Conversion
- Context Panel: What to wear, activity advice, real-world locations, and fun facts for every temperature zone.
- Milestone Timeline: From absolute zero to the surface of the Sun, with your temperature marked on the scale.
- Fever Checker: Visual body temperature gauge with color-coded zones and health advice (with medical disclaimer).
- Cooking Guide: Meat doneness, oven settings, and sugar stages — every temperature clickable to load in the converter.
- Mental Math Tricks: "Double it, add 30" for C→F. Perfect for travelers.
All conversions use exact mathematical formulas. 100% client-side — works offline, no data sent to any server. Try our Unit Converter for 200+ units across 15 categories.
Frequently Asked Questions
Use the formula: °F = (°C × 9/5) + 32. For example, 25°C = (25 × 1.8) + 32 = 77°F. For quick mental math: "Double it and add 30" — 25°C → 25×2 + 30 = 80°F (close to actual 77°F). Our converter shows the exact step-by-step calculation for any temperature you enter.
Kelvin is the SI unit of temperature, starting at absolute zero (-273.15°C) — the lowest theoretically possible temperature where all molecular motion stops. Scientists use Kelvin because it has no negative values, making calculations in physics, chemistry, and engineering simpler. To convert: K = °C + 273.15. Room temperature (20°C) = 293.15 K.
Normal body temperature ranges from 36.1°C to 37.2°C (97°F to 99°F). The commonly cited 37°C (98.6°F) is an average. Body temperature varies by age (children run slightly higher), time of day (lower in the morning, higher in the evening), measurement site (oral, armpit, rectal), and physical activity. Use our Fever Checker tab for a visual gauge.
Historical inertia and cultural familiarity. The US, along with a few other countries (Liberia, Cayman Islands), still uses Fahrenheit for everyday temperature. Attempts to switch to metric/Celsius in the 1970s didn't gain public adoption. Interestingly, Fahrenheit offers finer granularity for weather (0–100°F roughly covers the human-comfortable range), which some argue makes it more intuitive for daily weather.
Generally, 37.3°C (99.1°F) and above is considered a low-grade fever. 38.1–39°C is moderate fever, 39.1–40°C is high fever, and above 40°C requires immediate medical attention. However, "normal" varies by person and measurement method. Our Fever Checker provides a visual gauge with color-coded zones and general advice, though it is not a substitute for professional medical guidance.
Common oven settings: 150°C (300°F) for slow baking/casseroles, 180°C (350°F) for cakes and cookies (the most common setting), 200°C (400°F) for roasting vegetables, 230°C (450°F) for bread and pizza, and 260°C (500°F) for broiling. Our Cooking tab lists these and more — click any temperature to load it into the converter.
Absolute zero is -273.15°C (0 K, -459.67°F) — the theoretical lowest temperature where all molecular motion ceases. It cannot actually be reached, but scientists have cooled matter to within billionths of a degree of it. The Kelvin scale uses absolute zero as its starting point, which is why there are no negative Kelvin temperatures. You can see it on our Milestones timeline.
The page background uses CSS custom properties that change dynamically as you adjust the temperature. Nine temperature zones (extreme cold to beyond boiling) each have a unique color gradient and particle type. Smooth CSS transitions (1.2s) animate between zones. Particles (snowflakes, mist, sun rays, heat waves, steam, embers) use lightweight CSS animations — no heavy libraries. All visual, no data stored or transmitted.