Not an easy one to answer as guys deal-breaker will change depending on the guy.
It also depends on the girl's height as taller girls will have it spread out more so the same overweight won't necessarily look as bad.
Also it can depend on in part how pretty the girl naturally is to start with.
However, no one usually looks good if overweight male or female, but I think as the female form is supposed to be the more elegant (thin) then it may well look worse on women.
So a weight figure is hard to get too. But I would say non figuratively speaking anything that stands out as much if a bulge or makes you look pretty wide could be too much. Figuratively speaking I would say anything more than 200 pounds could quite likely be starting to get not a good sight to most men.
Sometimes below 200 pounds may not look that great but like I say above is dependent a bit on other factors. As a guy who finds obese women off-putting I think that many guys aren't going to get too concerned about a bit in the rear or thighs of a girl so long as it's only a little bit and not loads. Most guys aren't real Nazis on the subject but most expect something reasonable and will balk at women carrying around a lot of fat.
You have to understand that when a girl sees a girl he envisions being in bed 🛏️ with the girl. Girls that are obese the vision is not at all appealing in fact it is usually a dead turn off and a very unpleasant thing for a guy to contemplate. Again though if it's just a bit here & there while it's still not great it may not be stomach churning for him and still possible for him to see himself in bed with you.