Is Kelvin ever negative?

No — it's an absolute scale starting at 0 K (about −273.15°C), so Kelvin values are never negative in physical reality.

Can I enter Fahrenheit and convert the other way?

This tool takes Celsius as the primary input; for the reverse direction, solving the Fahrenheit formula backward gives the equivalent Celsius value.

Why does 273.15 show up in the Kelvin conversion?

It's the fixed offset between the Celsius and Kelvin scales — 0°C is defined as exactly 273.15 K, so adding that constant converts directly between the two.

What temperature is absolute zero?

0 K, equal to −273.15°C or −459.67°F — the theoretical point where a system has minimum thermal energy, and the reason Kelvin values never go negative in practice.

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Converters

Temperature Converter

Celsius, Fahrenheit, and Kelvin at a glance.

🔒 Runs entirely in your browser — nothing here is ever uploaded

About the Temperature Converter

Converts a Celsius value to Fahrenheit and Kelvin simultaneously, using the standard fixed conversion formulas between the three major temperature scales.

How to use it

Enter a value in the Celsius field.
Read the Fahrenheit and Kelvin equivalents in the readout.

Formula

°F = °C × 9/5 + 32
K = °C + 273.15

Worked example

25°C converts to 77°F and 298.15 K.

Recommendations

• 0°C (32°F) is the freezing point of water and 100°C (212°F) is the boiling point at standard pressure — handy reference points for sanity-checking a conversion.
• Kelvin has no negative values in practical use, since 0 K represents absolute zero.
• The gauge below the converter shows where a temperature falls among common comfort and weather zones at a glance.

Frequently asked questions

Fahrenheit was defined with different reference points than Celsius, so converting between them needs both a scaling factor and an offset, unlike the more direct Celsius-to-Kelvin relationship.

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