How do I convert 100 °C to °F?

(100 × 9/5) + 32 = 212 °F (boiling point of water).

Is 0 K the same as 0 °C?

No. 0 K = −273.15 °C (absolute zero). 0 °C = 273.15 K (water freezing point).

🔄 Conversion ⭐ Popular

Temperature Converter

Convert temperatures between Celsius (°C), Fahrenheit (°F), Kelvin (K) and Rankine (°R). Unlike most units, temperature scales have different zero points — this calculator handles the offsets correctly.

Last reviewed: January 2026 Formula shown No signup required

Educational estimate. Calculator results are for planning and information only, not financial, tax, medical, legal, or engineering advice. Verify important decisions with official sources or a qualified professional.

Temperature Converter

Celsius, Fahrenheit, Kelvin, Rankine

Value to Convert

Enter any number (decimals allowed).

From

📐 Formula & Method

Celsius ↔ Fahrenheit

°F = (°C × 9/5) + 32 | °C = (°F − 32) × 5/9

F freezes at 32 and boils at 212; C freezes at 0 and boils at 100.

Celsius ↔ Kelvin

K = °C + 273.15

Kelvin is an absolute scale with the same degree size as Celsius.

📋 How to Use

1
Enter the numeric value you want to convert.
2
Pick the source unit in the From dropdown.
3
Pick the target unit in the To dropdown.
4
Click Calculate. You will see the result, a full conversion table to every supported unit, and a list of common conversions.

💡 Key Insights

Water freezes at 0 °C / 32 °F / 273.15 K. Water boils (at 1 atm) at 100 °C / 212 °F / 373.15 K.
Absolute zero is 0 K = −273.15 °C = −459.67 °F = 0 °R — the theoretical lower limit of temperature.
The °F-to-°C "approximation" (subtract 30, halve) works in everyday ranges: 80 °F → ~25 °C; exact is 26.7 °C.
Rankine = Kelvin in Fahrenheit-sized degrees; common in US engineering thermodynamics.

🔬 Methodology & Accuracy

Formula: Linear unit conversion with high-precision constants. All math runs client-side in your browser using IEEE-754 doubles.

Data sources: BIPM SI brochure (9th ed.); NIST SP 811 (2008 ed.); ISO 80000-1 quantities and units.

Last reviewed: January 2026 · Accuracy: Results are precise to two decimal places using IEEE-754 double-precision arithmetic. Intended for educational and planning use only.

For informational purposes only. Results are estimates based on the inputs and formulas provided. For financial, tax, medical, or legal decisions, consult a qualified professional. Rates and regulations change — always verify current figures with official sources.

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❓ Frequently Asked Questions

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