How to make image size dynamic

[Kuper]

I have my own server
I have not used hosting for 10 years

[KarEm]

Hi,

...speed/performance, when loading big images.

What is also meant by that and, from my point of view, this is even more important, also consider the speed of mobile connections.Large images imply longer loading times and not every visitor wants to wait for the composition. In addition, mobile data connections are usually more expensive.Big images are for mobiles and tablets in my opinion disadvantageous.

Regards
KarEm