Temperature Converter

Convert Celsius, Fahrenheit, Kelvin, and Rankine instantly. All four scales update simultaneously with reference points for water freeze/boil, body temp, and oven settings.

Oven Settings, HVAC Setpoints, and Lab Reference Points

BrainyCalculators editorial insight — unique to this tool

Home ovens in the UK and US list Fahrenheit (350 °F ≈ 177 °C for baking) while most of the world sets Celsius — a 20 °C difference in proofing dough can ruin rise. HVAC technicians cross-reference °C setpoints on European equipment with °F thermostats in North America. Scientists use Kelvin for thermodynamics (0 K = absolute zero); Rankine appears in US aerospace and steam tables where Fahrenheit intervals are preserved on an absolute scale.

When to use this calculator

Reach for this converter when translating oven dials, weather forecasts, medical fever readings, or lab data between Celsius, Fahrenheit, Kelvin, or Rankine — not for cooking time or energy cost.

Reference	Value	Context
Water boils (sea level)	100 °C / 212 °F	Everyday reference
Human body (normal)	37 °C / 98.6 °F	Clinical baseline
Food-safe poultry internal	74 °C / 165 °F	USDA minimum
Liquid nitrogen	77 K / −196 °C	Lab cryogenics

Not what you need? For heat energy or electricity cost of heating, use Power Consumption. For weather wind chill, this tool only converts the temperature scale, not the composite index.

Converting length, weight, or multiple unit types?

This page converts temperature scales only. For length, mass, and more in one tool, use the Unit Converter →

Temperature (°C)

Celsius

—

°C

Fahrenheit

—

°F

Kelvin

—

Rankine

—

°Ra

What is a Temperature Converter?

Temperature conversion translates between °C, °F, K, and °Ra using offset and scaling formulas — not simple multiplication. 72°F room air is 22.2°C; 350°F oven is 177°C. Kelvin anchors absolute zero; Celsius and Fahrenheit are offset scales requiring both multiply and add/subtract 32.

Use this page for weather, cooking, HVAC setpoints, lab work, and science class. Temperature differences (ΔT) convert differently from absolute readings — ΔT in °C equals ΔT in K, but Fahrenheit differences need ×5/9.

For length (feet, metres) or mass (kg, lb), use the Length or Weight Converter. This page is thermal scales only. For multiple unit types together, use the Unit Converter.

Oven, Fever, and Lab Temperature Math

Recipe 350°F → °C: (350 − 32) × 5/9 = 177°C

Fever 38°C → °F: (38 × 9/5) + 32 = 100.4°F

Incubator 310 K → °C: 310 − 273.15 = 36.85°C

ΔT 10°C → ΔF: 10 × 9/5 = 18°F (no +32)

Use the full offset formula for absolute readings (oven dial, body temperature). Use multiply-only when converting a difference between two readings — a 10°C rise is 18°F, not 50°F.

Temperature Reference Points

Reference Point	°C	°F	K	°Ra
Absolute Zero	−273.15	−459.67	0	0
Water Freezes	0	32	273.15	491.67
Human Body Temp	37	98.6	310.15	558.27
Water Boils	100	212	373.15	671.67
Surface of the Sun	5,505	9,941	5,778	10,400

How the Temperature Converter Works

Formula, assumptions, and calculation steps for this conversion tool.

Methodology

Conversion calculators multiply by fixed conversion factors after identifying the source and destination units.

Calculation Steps

Choose the input unit and output unit.
Enter the amount to convert.
Apply the standard conversion factor.
Return the converted value with unit labels.

Assumptions and Limits

Conversions use standard factors unless a regional variant is selected.
Rounding is applied for readability.
Temperature and pressure conversions may require formulas rather than simple multiplication.

Frequently Asked Questions

What oven temperature is 350°F in Celsius?

350°F equals 177°C (often rounded to 180°C in recipes). Baking is sensitive to 10–15°C errors, so use the exact conversion rather than doubling Fahrenheit.

Why does Kelvin not use negative values?

Kelvin starts at absolute zero, the theoretical point where molecular motion stops. It is an absolute scale, so only offsets from Celsius matter: K = °C + 273.15.

Is a 1°C change the same as a 1 K change?

Yes for temperature differences. A rise of 5°C equals a rise of 5 K. The full conversion formula with +32 applies to absolute readings on the Fahrenheit scale, not to deltas.

What fever threshold should parents watch for?

Many clinicians treat 38°C (100.4°F) as a fever in children. Thermometers sold in the US often default to Fahrenheit while NHS guidance cites Celsius.

When is Rankine used instead of Kelvin?

Rankine appears in US thermodynamics and steam tables. It starts at absolute zero but uses Fahrenheit-sized degrees: °Ra = °F + 459.67.

Real-World Applications

🏨

Hotel Thermostats Abroad

A US room set to 72°F is about 22°C, while a European thermostat at 19°C feels like 66°F. Travelers use conversion to avoid overcooling or overheating unfamiliar controls.

🍰

Oven Settings Across Recipe Sites

American recipes list 350°F or 375°F; UK and EU ovens use Celsius. Converting to 177°C or 190°C prevents the common mistake of treating oven scales as roughly doubled.

🌡️

Fever and Clinical Notes

A temperature of 100.4°F equals 38°C, a common fever threshold. Parents and clinicians reading international guidance often need both scales side by side.

🥶

Cold Chain Shipping

Vaccines, seafood, and biologics have temperature windows such as 2-8°C or -20°C. Converting these limits accurately matters before using Fahrenheit-only loggers.

🧪

Lab Protocol Reproducibility

Incubators, water baths, and reaction notes may mix Celsius, Kelvin, and Fahrenheit in vendor manuals. Conversion keeps experiments aligned with published conditions.

🔥

HVAC and Heat-Pump Specs

Equipment datasheets quote ambient test temperatures in different scales. Converting setpoints and outdoor design values helps compare COP, capacity, and defrost behaviour.

Temperature Conversion Mistakes to Avoid

Forgetting the 32°F offset

Multiplying Celsius by 1.8 without adding 32 turns 20°C into 36°F instead of 68°F. The offset exists because the two scales anchor zero at different physical points.

Applying full formulas to temperature differences

A 10°C swing equals 18°F, not 50°F. Differences scale by 1.8 only; the +32 term cancels when you subtract two converted readings.

Treating Celsius and Kelvin as identical numbers

25°C is 298.15 K, not 25 K. Using Celsius values in gas-law or thermodynamic equations produces meaningless results.

Using mental shortcuts in lab or HVAC work

Double-and-add-30 is acceptable for weather chat but not for incubator setpoints, vaccine cold-chain limits, or heat-pump defrost curves.

Misreading negative values across scales

−10°C is a cold winter day (14°F), while −10°F is dangerously cold (−23°C). Only −40° is numerically equal on both scales.

Key Temperature Reference Points

Reference Point	°C	°F	K
Absolute zero	−273.15	−459.67	0
Water freezes	0	32	273.15
Body temperature	37	98.6	310.15
Water boils (sea level)	100	212	373.15
Steel melts	~1,370	~2,500	~1,643

References

BIPM. The International System of Units (SI Brochure), 9th edition. bipm.org, 2019.
NIST. SI Unit of Thermodynamic Temperature: Kelvin. nist.gov, 2019.
Chang, R. and Overby, J. General Chemistry: The Essential Concepts. McGraw-Hill, 2019.
WMO. Guidelines on Climate Metadata and Homogenization. wmo.int, 2003.
Atkins, P. and de Paula, J. Physical Chemistry. Oxford University Press, 2014.