How to change decimal symbol and digit grouping symbol in Windows 10

See Change the decimal point to a comma or vice versa for Excel.

A decimal symbol or decimal separator is a symbol used to separate the integer part from the fractional part of a number written in decimal form. This symbol can be a period or a comma.

For ease of reading, numbers with many digits may be divided into groups using a digit grouping symbol, such as comma, dot, space, etc.

To see or change pre-defined in Windows 10 decimal symbol and digit grouping symbol, do the following:

   1.   Open Control Panel.

See How to open Control Panel in Windows 10.

   2.   In the Control Panel dialog box, choose Change date, time, or number formats:

   3.   In the Region dialog box, choose Additional settings...:

   4.   In the Customize Format dialog box, choose appropriate value from the list Decimal symbol and/or Digit grouping symbol, or enter the new one:

   5.   After clicking the Apply button, you can see how Windows will show amounts in the Example group in the bottom of the dialog box:

See also this tip in French: Comment changer le symbole décimal et le symbole de groupement de chiffres dans Windows 10.