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Celsius Converter

Convert temperatures in Celsius to Fahrenheit or Kelvin and back.

Formula shown0 inputs definedUpdated Nov 2025By CalcuTotal TeamFree, no sign-up

Quick Summary

Use this when you need:

Translate weather reports from Celsius to Fahrenheit
Convert lab setpoints between °C and K
Teach the relationship between Celsius and Fahrenheit intercepts

You’ll get:Temperature

How this is calculated

Formula:

F = C * 9/5 + 32; K = C + 273.15

In plain language:

Celsius is linked to Fahrenheit by a 9/5 slope with a 32° offset, and to Kelvin by adding 273.15. Inverse operations subtract the offsets and rescale.

The formula is always visible so you can verify the math and explain your numbers to anyone who asks.

What these terms mean

Temperature

Temperature used in the calculation.

When to use this calculator

Translate weather reports from Celsius to Fahrenheit
Convert lab setpoints between °C and K
Teach the relationship between Celsius and Fahrenheit intercepts

Last updated: November 22, 2025

Celsius converter explained

Use this converter to flip temperatures between Celsius, Fahrenheit, and Kelvin. It helps when recipes, lab gear, and weather feeds use different scales but you need consistent numbers.

How the conversion works

Celsius links to the other scales with simple affine formulas:

\text{°F} = \text{°C} \times \tfrac{9}{5} + 32

K = \text{°C} + 273.15

Inverse directions follow by isolating °C:

\text{°C} = (\text{°F} - 32) \times \tfrac{5}{9}

\text{°C} = K - 273.15

Units and conversions

Scale	Symbol	Relation
Celsius	°C	base for this view
Fahrenheit	°F	°F = °C × 9/5 + 32
Kelvin	K	K = °C + 273.15

Worked examples

Mild day Given 18 °C:
$\text{°F} = 18 \times \tfrac{9}{5} + 32 = 64.4\,\text{°F}$ $K = 18 + 273.15 = 291.15\,\text{K}$
Result: 64.4 °F, 291.15 K.
Freezer check Given -10 °C:
$\text{°F} = -10 \times \tfrac{9}{5} + 32 = 14.0\,\text{°F}$ $K = -10 + 273.15 = 263.15\,\text{K}$
Result: 14.0 °F, 263.15 K.

Tips and pitfalls

Kelvin never goes below zero; if you see a negative K, a formula sign flipped.
Use at least one decimal place for weather; keep two for lab work.
When converting temperature differences, a change of 1 K equals a change of 1 °C, but not 1 °F.

References and further reading

Frequently Asked Questions

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Calculator info

Version:: v1.0.0
Last reviewed:: Nov 22, 2025
Sensitivity:: low
References:: 1

Last updated: November 22, 2025

Celsius converter explained

Use this converter to flip temperatures between Celsius, Fahrenheit, and Kelvin. It helps when recipes, lab gear, and weather feeds use different scales but you need consistent numbers.

How the conversion works

Celsius links to the other scales with simple affine formulas:

\text{°F} = \text{°C} \times \tfrac{9}{5} + 32

K = \text{°C} + 273.15

Inverse directions follow by isolating °C:

\text{°C} = (\text{°F} - 32) \times \tfrac{5}{9}

\text{°C} = K - 273.15

Units and conversions

Scale	Symbol	Relation
Celsius	°C	base for this view
Fahrenheit	°F	°F = °C × 9/5 + 32
Kelvin	K	K = °C + 273.15

Worked examples

Mild day Given 18 °C:
$\text{°F} = 18 \times \tfrac{9}{5} + 32 = 64.4\,\text{°F}$ $K = 18 + 273.15 = 291.15\,\text{K}$
Result: 64.4 °F, 291.15 K.
Freezer check Given -10 °C:
$\text{°F} = -10 \times \tfrac{9}{5} + 32 = 14.0\,\text{°F}$ $K = -10 + 273.15 = 263.15\,\text{K}$
Result: 14.0 °F, 263.15 K.

Tips and pitfalls

Kelvin never goes below zero; if you see a negative K, a formula sign flipped.
Use at least one decimal place for weather; keep two for lab work.
When converting temperature differences, a change of 1 K equals a change of 1 °C, but not 1 °F.

Quick Summary

Calculator Tool

How this is calculated

What these terms mean

Temperature

When to use this calculator

Celsius converter explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

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Calculator info

Celsius converter explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

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