Remembering size web sites are displayed?

It seems that I am continually changing (enlarging) the size that web sites are displayed on my 27” iMac.

So what I am looking for is an app that will allow me to set the size (preference?) of the various sites I regularly visit, so that each time I visit that site, it is displayed as I prefer.

I have been unsuccessful in finding such a critter. Does anyone know a resolution to my vexing problem?