CONVERT in Excel: Units, Temperature and Binary Prefixes

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• Checked: October 14, 2026; official CONVERT reference. Documentation and independent models; no native Excel execution or wider platform certification.

=CONVERT(number,from_unit,to_unit)

Supply unit codes as quoted text or references to cells containing those codes. Microsoft documents #VALUE! for invalid input types and #N/A for an unknown unit, an unsupported binary prefix or incompatible groups.

The function does not determine what a raw number measures. A value of 12 could represent inches, hours or bytes; the from_unit argument supplies that meaning. A mathematically valid conversion can still be wrong if the original unit was mislabeled.

Enter this table in A1:C5. In D2 use =CONVERT(A2,B2,C2) and fill through D5:

The independent factors are 2.54 centimeters per inch, 0.3048 meters per foot, 1.609344 kilometers per statute mile and 1000 meters per kilometer. Keep both unit columns in the report so the results remain interpretable.

For a round-trip control, =CONVERT(D3,"m","ft") returns the modeled original 5 feet. Small floating-point display differences in a native client would need tolerance-based checking; this guide does not promise bit-for-bit reversibility.

=CONVERT(20,"C","F")
=CONVERT(68,"F","C")
=CONVERT(0,"C","K")

The modeled outputs are 68, 20 and 273.15. The Celsius-to-Fahrenheit relation is F=1.8*C+32. A temperature reading of 20 degrees Celsius is therefore not converted by multiplication alone.

A temperature difference is a different quantity. A rise from 10 to 20 degrees Celsius corresponds to converted readings 50 and 68 degrees Fahrenheit, a difference of 18. Directly converting the number 10 as a Celsius reading gives 50, not the 18-degree Fahrenheit change. Convert both endpoints and subtract, or use a separately justified interval conversion.

Microsoft lists byte and bit, metric prefixes such as k and M, and binary prefixes such as ki and Mi. Their capitalization is part of the code.

For the fourth result, 2*2^20/10^6=2.097152. A label that says only “MB” without specifying the intended convention can hide a meaningful difference. Store the exact code in the workbook instead of guessing from a familiar abbreviation.

Use =CONVERT(100,"ft2","m2") for 100 square feet. The independently computed result is 9.290304 square meters, since 100*(0.3048^2)=9.290304.

By contrast, =CONVERT(100,"ft","m") gives 30.48 meters, a length. That number is not the area conversion. Microsoft’s page also demonstrates applying the length factor twice; explicit squared-unit codes make the intended dimension easier to review.

=CONVERT(1,"m","sec") has documented #N/A because distance and time are different groups. Unknown codes are not automatically interpreted as similar unit names. For example, the documented inch code is in; an arbitrary spelling such as inches is not on the accepted list.

Use ISNUMBER to distinguish successful numeric results from error handling, and ROUND only when a downstream display or measurement policy calls for rounding. Do not round every intermediate conversion before totaling values.

The worked factors and dimensions are independently calculated, while unit-code eligibility comes from Microsoft’s current table. Very large prefixes, overflow, unusual coercions and native precision boundaries are not tested here. CONVERT performs measurement conversion, not currency exchange or an inference about the accuracy of the original measurement.

• Microsoft CONVERT reference.
• Editorial testing standards.

Expected outputs are independently calculated examples or documented rules, not captured native Excel results. Formulas use English function names and comma argument separators. Locale, rendering and boundary restrictions are stated where relevant.