Regex max 100 2 digits

I want to do a regex to have a maximum number of 100 with 2 decimals

I made the following regex:

^\d *\,\d{0.2}$

my problem : I can only put a comma (ex: 100,00) but if I put a dot it does not work (100.00) i tried to change my regex with ^\d *\,.\d{0.2}$ but i have the same problem

how can I do ?

thank you