object vs. iframe

Why not let WordPress handle the embeds?

I need to define a width and height.

You can set the width and height by going to Settings > media in your admin.

You can do that from Settings>>> Media

Yes, but what about this: ” It also allows you to set a maximum (but not fixed) width and height, like so: [embed width="123" height="456"]…[/embed]“

So I suppose I can not determine a precise width and height?

Maybe I misread it. My English … (I’m Danish – and school is long ago. I use google to translate with ??

“a maximum (but not fixed)”

I have incidentally also pages with videos of various size.