English grammar and punctuation can be a constant learning curve, whether you’re a native speaker or learning English as a second language.
You might think you’ve uncovered every quirk and anomaly there is, but then something else crops up that you’ve never encountered before.
Using periods and commas in the world of numbers is something that we get asked about a lot. Both periods and commas are used as decimal markers, and this guide will tell you which one you should be using.
What Is a Decimal Marker?
A decimal marker (i.e. a decimal separator, decimal sign, or radix character/point) is a symbol used to separate the integer and fractional parts of a number. In 2.3, 2 is the integer (i.e., a whole number) and 3 is the fractional part.
A decimal marker can be either a period or a comma.
Period: 2.3
Comma: 2,3
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When a period is used as a decimal marker, it’s called a decimal point. When a comma is used as a decimal marker, it’s called a decimal comma. Both are decimal markers.
Should You Use a Period or a Comma as a Decimal Marker?
Depending on where you live, the standard practice for which decimal separators you should use will differ.
In the United States and the United Kingdom, periods are used as decimal separators instead of commas. On the other hand, Russia, Croatia, Peru, and Turkey (to name a few) use decimal commas.
See the complete list of countries that use decimal commas and those that use decimal points.
Chances are, people will understand your intention, regardless of whether you use a decimal point or a decimal comma. But, for the sake of accuracy, it’s best to choose the decimal marker that is the standard in your country.
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