Here are some tell-tale signs:

Headshot pics only or generally pics that obscure her body in some way.

List best feature as "my smile" or "my eyes" etc. A attractive girl who is body confident will always put her arse tits or legs as best feature.

Girls who list their personal qualities as "kind" "loving" "genuine" and other fluffy bunny type words, attractive confident women tend to use harder more aggressive terms like "sassy" "driven" "ambitions" etc, they arn't trying to sell themselves on their personality because they know they don't have to.

They say "my friends say I am ....", an attractive girl just says "I am ..."

There is an undercurrent of confidence in the way an attractive girl presents herself and in her communication. You get attuned to it after a while.

gawd ive done so much online stuff over the years its insane, i must have bummed 150 girls from online - ive had dates with munters and fitties -- over the years online datings changed.

Ive realised that its best to forget online and get out there in the real world.
In reality you can walk into a bar-- see what IOIs youa re getting from girls and walk up to them for a banter if they are what you are interested in.
Rather than spending time messaging a hot chick online who already has 30 messages that day from other guys.

its actually funny because if you asked me this question a month ago i would ahve said the opposite

It really does make good sense chaps.

They may as well write "boring", "insecure" and "fat"