Centigrade to Celsius Converter
Convert between two names for the same temperature scale with a precise 1:1 identity.
The startup example is ready to export.
Temperature inputs
Enter a decimal number using a period, such as 17 or -12.5.
You may edit this field too; the centigrade value updates instantly.
Live result
17 °centigrade = 17 °C
The numerical value does not change because centigrade and Celsius denote the same scale.
17 degrees centigrade equals 17 degrees Celsius.
How to use the centigrade to Celsius converter
What this calculator does. This converter expresses a temperature written in “degrees centigrade” as degrees Celsius, or performs the same operation in reverse. The result is an exact numerical identity: a value of 17 degrees centigrade is 17 °C, with no multiplication factor and no offset. It is useful for interpreting older documents, equipment labels, recipes, laboratory notes, weather records, and translations that use the historic word “centigrade.” It does not estimate measurement uncertainty, correct a thermometer, or convert to Fahrenheit or kelvin.
When to use it. Use the converter when you need to modernize centigrade wording in a report, check whether an older temperature specification matches a Celsius requirement, prepare consistent labels for a dataset, or reassure a reader that the two names refer to the same scale. The NIST guide to SI temperature units explains the degree Celsius and its relationship to the kelvin.
How to calculate. The calculator opens with a complete demonstration: 17 degrees centigrade and 17 °C. Its example Excel workbook is immediately available.
- Replace the value in Temperature in centigrade with the number you want to express in Celsius. The Celsius field and every result update live.
- Alternatively, edit Temperature in Celsius. The centigrade field updates with the same numerical value, so the tool works in both directions.
- Read the equality in Live result, then check the two value cards and the Difference card. A valid conversion always has a difference of 0°.
- Select Download Excel to create a current-state .xlsx workbook with the inputs, exact identity, outputs, units, and explanatory notes.
- Select Reset to clear both demonstration values and all calculated content. Download Excel is then disabled until you enter a complete valid value again.
Input guide. Temperature in centigrade is a required decimal temperature. Enter a plain number with an optional leading minus sign and a period as the decimal separator, for example -12.5. Do not include a degree symbol, unit text, commas, or scientific notation. Higher or lower input values produce exactly the same higher or lower Celsius number. A common mistake is assuming that “centigrade” requires a Fahrenheit-style formula; it does not. Temperature in Celsius follows the same accepted format and is also an editable conversion source. For example, typing 34 produces 34 degrees centigrade. Only one valid field is needed during editing because the calculator immediately synchronizes the other field.
Output guide. Live result states the full equality and is an exact conversion identity, not an estimate. Centigrade value and Celsius value display the same canonical number at a practical precision of up to six decimal places. Difference measures Celsius minus centigrade and is always 0° for valid input, including negative temperatures and zero. The Ratio: 1:1 pill records the unchanged scale factor, Offset: 0° records the absence of an additive adjustment, and the status pill indicates whether the current state is valid. The formula line, °C = °centigrade, shows the operation used by the model.
Worked example. The startup value is 17 degrees centigrade. Applying the identity formula gives 17 × 1 + 0 = 17 °C. The first-open result therefore reads “17 °centigrade = 17 °C,” both value cards show 17, and Difference shows 0°. The workbook uses those same typed values rather than copying rounded screen text.
Learn more. For the formal international definition, the BIPM history and resolutions for thermodynamic temperature includes the 1948 adoption of the name “degree Celsius.”
Why the conversion is one-to-one
“Centigrade” was the older descriptive name for the hundred-step temperature scale. “Celsius” is the modern name used in the International System of Units. Renaming the scale did not alter its graduations, so the numerical value stays unchanged. This differs from converting Celsius to Fahrenheit, where both a scale factor and an offset are necessary.
The degree Celsius has the same interval size as the kelvin. Celsius temperature is related to thermodynamic temperature by an offset of 273.15, but that relationship is separate from the centigrade-to-Celsius naming conversion. The NIST introduction to the kelvin gives practical reference points and explains why a one-kelvin change equals a one-degree-Celsius change.