MetricCalc

Temperature conversion hub

Temperature Converter

Convert Celsius, Fahrenheit, Kelvin, Rankine, and Reaumur in one place. The converter shows the main result first, compares the same reading across other scales, and includes the water triple-point reference for specialist work.

Scales + reference Instant swap Live result

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-100 Value in selected source scale 500

Common starting points

Temperature at a glance

Compare everyday, scientific, thermodynamic, historical, and reference-point scales without leaving the page.

weather + science

77

Fahrenheit (degF)

Colder Reference Hotter

Source

Celsius (degC)

Direction

Live conversion

Target

Fahrenheit (degF)

Equivalent values across scales and reference

Useful when a weather value, lab reading, or engineering note needs more than one scale.

degC

-

Celsius

degF

-

Fahrenheit

K

-

Kelvin

degR

-

Rankine

degRe

-

Reaumur

x TPW

-

Water triple-point multiples

The x TPW value is a multiple of the water triple-point reference, with 1 x TPW treated as 273.16 K in this converter. It is not a conventional temperature scale.

Scale and reference shortcuts

tap any option

Interpreting temperature results

Four Details That Can Change What a Temperature Means

A converted temperature is only useful when its original meaning stays intact. Before using the result, check whether the source describes an actual temperature reading or a temperature change, how precise the measurement is, and whether pressure, material behavior, or physical limits affect the value.

Reading or Interval?

A temperature reading and a temperature change are not converted in the same way. For example, a reading of 10°C converts differently from an increase of 10°C. Scale offsets apply to actual readings, not to the size of a temperature change.

Converted Digits Are Not New Accuracy

A converted result may show several decimal places, but that does not make the original measurement more precise. If a sensor was rounded to the nearest degree, the converted value should be treated with the same level of accuracy.

Boiling Point Depends on Pressure

Water boils at 100°C only near standard atmospheric pressure. At higher elevations, where air pressure is lower, water boils at a lower temperature.

Air and Surface Readings Can Differ

A wall, pan, pipe, roof, or road surface may be much hotter or colder than the surrounding air. Always record what the sensor actually measured so the converted temperature keeps the right context.

Popular Temperature Converters

Start with these common temperature conversions for weather, cooking, lab values, dashboards, HVAC notes, and thermodynamics.

C

Celsius to Fahrenheit

Convert weather, cooking, and room temperatures from degC into degF.

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F

Fahrenheit to Celsius

Turn US temperature readings into Celsius for travel, weather, recipes, and reports.

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K

Celsius to Kelvin

Move from everyday Celsius readings into the absolute scale used in science.

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K

Kelvin to Celsius

Translate lab, physics, and sensor values into a Celsius temperature people can read quickly.

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F

Fahrenheit to Kelvin

Convert Fahrenheit readings into Kelvin for engineering notes and scientific calculations.

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K

Kelvin to Fahrenheit

Convert absolute temperature values into Fahrenheit for US-facing dashboards and labels.

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R

Celsius to Rankine

Use when a Celsius value needs to be written on an absolute Fahrenheit-sized scale.

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R

Rankine to Celsius

Convert Rankine values back into Celsius for easier reading and reporting.

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R

Fahrenheit to Rankine

Shift Fahrenheit readings into Rankine for thermodynamics and engineering references.

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F

Rankine to Fahrenheit

Bring Rankine values back to Fahrenheit for US customary temperature context.

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K

Kelvin to Rankine

Convert between the two absolute temperature scales used in science and engineering.

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R

Rankine to Kelvin

Bring Rankine temperatures into Kelvin for equations, lab notes, and SI-based reporting.

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Re

Celsius to Reaumur

Convert Celsius into the Reaumur scale when working with older references or archival material.

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Re

Reaumur to Kelvin

Convert the historical Reaumur scale into Kelvin for archival or technical comparisons.

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TPW

Triple Point of Water to Kelvin

Convert water triple-point multiples into Kelvin using 273.16 K as the reference value.

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Which Temperature Scale Fits Best?

A useful temperature conversion should do more than return the correct number. It should also make sense in the situation where the value will be used. For example, a weather app, recipe, classroom exercise, lab report, and turbine calculation may all involve temperature, but each one may need a different scale to make the result clear, practical, and easy to interpret.

Task Best scale Why it works Helpful converter
Weather and travel degC or degF These are the scales most people expect in forecasts and thermostats. Celsius to Fahrenheit
Cooking and ovens degF or degC Recipes and appliance manuals often use different regional scales. Fahrenheit to Celsius
Science and labs Kelvin Kelvin is appropriate for equations that require absolute temperature. Celsius to Kelvin
US engineering notes Rankine Rankine uses Fahrenheit-sized degrees on an absolute scale. Fahrenheit to Rankine
Historical references Reaumur Reaumur appears in older scientific and food-processing material. Reaumur to Kelvin

Helpful Temperature Reference

Temperature conversions are easier to understand when you know a few key reference points.

Celsius and Kelvin use the same size degree steps, but they begin from different zero points. Fahrenheit differs in both ways: it uses a different degree size and a different starting point.

Because of these differences, temperature conversion is not always a simple multiplication. In many cases, the formula also needs an added or subtracted offset to produce the correct result.

Reference point Celsius Fahrenheit Kelvin Rankine
Absolute zero -273.15 degC -459.67 degF 0 K 0 degR
Water freezes near standard pressure 0 degC 32 degF 273.15 K 491.67 degR
Example room temperature 20 degC 68 degF 293.15 K 527.67 degR
Water boils at standard atmospheric pressure 100 degC 212 degF 373.15 K 671.67 degR

Rounding Temperature Values the Right Way

Round temperature values according to how the result will be used. For a weather card, whole degrees are usually clear enough. For cooking, use the oven temperature setting shown on the appliance. For a lab report, match the precision of the measuring instrument. When calculating average temperatures, keep the full values during the calculation and round only the final result before displaying it.

Temperature Sources and Scope

These tools are designed for temperature scale conversions, not heat energy, heat transfer, or weather index values such as heat index or wind chill. If you need to convert distance, use the length converters. If you need liquid capacity or volume, use the volume converters. For measurement reference, the SI Brochure maintained by BIPM defines the kelvin as an SI base unit, while NIST provides guidance on SI usage and US measurement practices.

Questions About Unusual Temperature Results

Can a temperature go below 0 Kelvin?

No. 0 Kelvin is absolute zero, the lowest point on the Kelvin scale. If a conversion shows a negative Kelvin value, the input is outside the normal physical temperature range and should be checked.

Why are Celsius and Fahrenheit equal at -40?

Celsius and Fahrenheit use different zero points and different degree sizes, but their conversion lines meet at -40. That is why -40°C and -40°F describe the same temperature.

What does TPW mean in this converter?

TPW means the triple point of water. In this converter, 1 TPW is treated as 273.16 K, and 2 TPW is treated as 546.32 K. This option compares multiples of that reference value. It is useful as a scientific reference, but it should not be treated as a conventional everyday temperature scale.