¡La Esquina de la Gramática! Rule 30

Decimals: Comma or period? Both are valid

The sign to separate decimals when expressing a number in digits can be a period or a comma.

In Mexico and the Caribbean a period is more commonly used, while a comma is mostly used in Spain.

The book La ortografía de la lengua española advises unification so it suggests using a period (once y medio: 11.5), but it also notes than when a comma is used, it shouldn’t be considered a mistake (once y medio: 11,5).

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