Temperature conversion

The temperature calculator allows quick conversion of values between degrees Celsius (°C), Fahrenheit (°F), and Kelvin (K). Just enter the value, select the input and target units, and the tool will immediately convert the temperature according to the appropriate formulas. It is useful both for analyzing device parameters and in everyday applications, e.g., comparing data from technical documentation and standards.

What is the temperature calculator used for?

The TME temperature calculator helps to quickly and accurately convert values given in different scales, which is especially important when working with documentation and components from markets with different standards. In practice, it comes in handy, for example, when a datasheet of a component from the USA gives the operating range in °F, while the whole project is conducted in °C, or when laboratory test specifications contain values in Kelvins. Instead of memorizing formulas and converting manually, you can immediately enter the value into the calculator and get the result in the correct unit.

Using the tool reduces the risk of calculation errors, which may lead to incorrect assessment of the devices' working temperature limits, improper component selection, or incorrect parameter settings in cooling and heating systems.

Temperature units – a brief overview

Degrees Celsius (°C)

Degrees Celsius is the most commonly used temperature unit in Europe and in most technical documentation related to electronics, automation, and installations. The Celsius scale is based on the properties of water: 0°C corresponds to the freezing point of water, and 100°C to its boiling point (at atmospheric pressure at sea level). This makes it intuitive for everyday use and convenient for describing ambient temperature, device operation, or technological processes.

Degrees Fahrenheit (°F)

Degrees Fahrenheit are mainly used in the United States and a few other countries, both in daily weather forecasts and some technical documentation. In this scale, the freezing temperature of water is 32°F and boiling is 212°F. The conversion between °C and °F is not a simple linear multiplier – it requires both scaling and shifting the zero point, so the calculator is a clear convenience here.

Kelvins (K)

Kelvin is a temperature unit in the SI system, primarily used in physics, engineering, and documentation related to precise measurements. The Kelvin scale starts at the so-called absolute zero (0K), equivalent to -273.15°C. Temperature differences in Kelvins and Celsius degrees have the same numerical value (a change of 1K equals 1°C) – only the scale’s starting point differs. Because of this, Kelvins are convenient for calculations related to thermodynamics, radiation, or material characteristics.

How does temperature conversion work?

Temperature conversion differs from converting quantities like length or mass because it requires not only multiplying by a coefficient but also considering the shift of the zero point of the scale. Between the Celsius and Kelvin scales, the relationship is simple: add a constant to the °C value to get Kelvins. Conversely, to convert from Kelvin to Celsius, subtract that value.

Conversion between °C and °F is a bit more complex because the scales have different increments (different “density” of degrees) and different zeros. The approximation “30°C is about 86°F” may suffice for weather forecasting, but when designing a cooling system or analyzing the maximum operating temperature of a component, greater accuracy is necessary. The calculator automatically applies the appropriate relationships, so you don't have to memorize formulas or worry about the order of operations. This tool lets you focus on interpreting results – for example, checking whether a particular temperature is within the permissible operating range of a system – instead of on the conversion process itself.

Practical uses of the temperature calculator

The temperature calculator is useful wherever temperature matters for equipment function, processes, or user comfort. In electronics and automation, it allows quick verification of whether components with a specified operating range given in °C or °F will perform well in a given environment. It also facilitates comparing datasheets from manufacturers from different world regions who use different units. In HVAC, cooling, and heating systems, the calculator helps convert settings and values from project documentation into parameters used in local standards. In laboratories, it is used to convert temperatures given in Kelvins into more intuitive degrees Celsius and vice versa. This tool can also be helpful in simpler tasks, such as interpreting graphs, comparing standards, or configuring temperature sensors in controllers.

FAQ – most common questions about temperature conversion

Why do US documents specify temperatures in °F?

In the USA, the imperial system is still used in everyday life and many industries, along with the Fahrenheit scale (°F) – both in weather forecasts and some technical documentation. For local users, the 0…100°F range feels more "familiar" than 0…40°C. Therefore, US manufacturers often stick to °F, and users in other countries must convert values to °C – this is where the temperature calculator helps.

How to ensure the component temperature range is correctly converted?

The simplest way: convert the values using the calculator and compare the result with the original datasheet note. Check the following details:

whether both ends of the range are converted (eg. -40 and +185°F),
whether the units are consistent throughout the project (either all °C or all °F),
whether after rounding, the result still fits within the manufacturer’s official range.

If something "does not fit," it’s better to check the documentation again than accept the value “by guess.”

Can Kelvin values be used instead of °C in technical projects?

You can, but it is not typical in daily project documentation. Kelvins are very convenient in calculations (e.g., thermal, physical, radiation-related), but project requirements, standards, component operating ranges, and device settings are almost always given in °C. A sensible workflow is: calculations in K, communication and documentation in °C.

Why do some graphs (e.g., LED diode characteristics, power transistors) have the temperature axis in Kelvins, and others in °C?

Graphs with the Kelvin axis appear where temperature directly enters physical equations (e.g., semiconductors, radiation, thermal noise). For a designer who wants to know “will this diode withstand 85°C in the casing?”, graphs in °C are more convenient because they are easy to compare with ambient temperature and the range from the datasheet. That is why documentation often mixes both approaches: models and theory are shown in K, while practical user graphs are in °C.

How to convert temperature units manually?

If you can't use our temperature calculator that quickly does it for you, remember the following formulas:

Formula to convert degrees Celsius to degrees Fahrenheit

Formula to convert degrees Celsius to Kelvins

Formula to convert degrees Fahrenheit to degrees Celsius

Formula to convert degrees Fahrenheit to Kelvins

Formula to convert Kelvins to degrees Celsius

Formula to convert Kelvins to degrees Fahrenheit

Did you know…

Anders Celsius originally defined 0°C as the boiling point of water and 100°C as the freezing point. Only later did other scientists invert the scale to the form we know – so that “up” means warmer, not colder.
-40°C and -40°F are exactly the same temperature. At this single point, the Celsius and Fahrenheit scales “meet.” It is a good test to check whether the conversion formula is used correctly.
Absolute zero (0K, i.e., -273.15°C) is the temperature at which particles have minimal possible energy. In practice, it cannot be reached, but it can be approached very closely in laboratories.
The Celsius scale is linked to the freezing and boiling points of water, which is very intuitive in everyday life. Kelvins, on the other hand, work great in physical equations – absolute zero is a much more convenient starting point than water’s freezing temperature.
Fahrenheit invented his scale with three reference points. One was supposed to be a mixture of ice, salt, and water (0°F), the second about the temperature of the human body, and the third the freezing point of pure water (32°F). This sounds unintuitive today, but back then it seemed quite practical.
The surface temperature of the Sun is better presented in Kelvins. Saying the Sun has about 5500°C is correct, but physicists prefer 5800K – it is easier to insert this value into equations describing radiation and spectrum.
Ice can melt below 0°C! If you press skates on ice strongly enough, pressure lowers its melting point. That’s why a thin steel edge slides over a very thin water layer. In practice, the effect is a bit more complex, but it sounds like thermal magic.
“Cold” metal and “warm” wood can have the same temperature. When touching a metal handle and a wooden railing, the metal seems colder. In reality, both materials have the same temperature, but metal conducts heat better and draws it faster from your hand. Similarly, when you open the oven and reach into the hot air – nothing happens, but touching a tray heated to 200°C means preparing for burn treatment. The temperature is the same, but metal also “gives off” heat much better than air, so the skin absorbs energy much faster.
Coffee “at room temperature” is always too cold. Room temperature is conventionally about 20–25°C. For electronics – perfect. For an engineer reaching for cooled coffee – an unpleasant surprise.
On the summit of Mount Everest, water boils at a lower temperature than in a kettle at home. At an altitude of ~8848m, atmospheric pressure is so low that water boils around 70°C. For liquid-cooled electronics or industrial processes, this is very important – “boiling temperature” is not a universal value.
A hot processor can heat an entire room… slowly but effectively. A computer with 500W power consumption turns a large part of that power into heat. If it runs for a long time in a small room, it realistically raises the ambient temperature – just like a small electric heater of similar power.
In many standards, “high temperature” starts much earlier than we might think. For humans, 60°C is “hot water.” For electronics, above 85°C is the range where many components already have reduced lifespan. Special high-temp elements (e.g., 125°C, 150°C) are treated as a separate class.
Freezing electronics is not always a good idea. Although lower temperature reduces thermal noise and the resistance of some materials, too low temperatures can cause solder cracking, differences in material expansion, and moisture condensation problems when returning to normal conditions.