Or
[Ctrl] [mouse wheel].

Also it is better to change the size of your system fonts, icons etc too.

Crtl +

Hi, if you use desktop computer with Windows simple press Ctr +

Sorry:) I just followed Kieran's invitation:)

Most web browsers have the capability of enlarging text. It's not the perfect answer but it's better than nothing. Find the actual name of the web browser you are using, and then Google on something like

enlarge text microsoft edge

or 

enlarge text firefox