I would say Big Macs. Too much lettuce...

McDonalds.

Mickey D's for sure

I'd go with Mickey D's as well. That's just because Wendys is considerably awesome.

" Mickey D's for sure "  

McDonalds. They aren't awful, but they aren't very good.

I know In-n-out burgers are AMAZING,  but i would probably have to go with mcdonalds burgers.

Definitely McDonalds. While I do  like McD's on occasion, everything else is just so much better.

McDonalds. Not terrible, but not good either.

" I would say Big Macs. Too much lettuce... "

Sonic. Ugh.

Sonic or McDonald's.  Probably McDonald's.  I still can thoroughly enjoy a burger from there though.

McDonalds. Don't get me wrong; they are still very good in my opinion, but not as good as Wendy's or Burger King's burgers.

mcdonalds cheeseburger, hate those diced onions.

I found Mcdonalds burgers taste close to the taste of shit, I WOULD KNOW.
 
DQ's Flamethrower was the best fast food burger I ever had.

I ordered 20 double cheeseburgers from McDonald's once.  So those.

When I ate meat, I thought White Castles had atrocious burgers

McDonalds or Sonic's. Both taste flavorless & greasy as hell, but I'd eat them if I'm starving and there's nothing else around.

" When I ate meat, I thought White Castles had atrocious burgers "

" Arby's. "

Burger King.  I don't know what it is about their meat but it has a flavor I don't appreciate.  

" @MurderByDeath: They have a thing called the Roast BURGER and it's fucken disgusting.   Arby's. "

i only eat the BK chicken fries........

mcdonald's is probably the worst but their breakfast stuff is pretty good, need to serve that shit all day yo.

" I would say Big Macs. Too much lettuce... "

oh wait, just remembered my 2006 encounter with the McBand-aid  *shivers*

McD's.

" @MurderByDeath: They have a thing called the Roast BURGER and it's fucken disgusting.   Arby's. "

mcdonald's and burger king are both pretty bad when comparing to wendy's

McDonald's burgers get my vote. I'm not sure if I could single out one specific worst burger, though.

" McDonalds or Sonic's. Both taste flavorless & greasy as hell, but I'd eat them if I'm starving and there's nothing else around. "

Anything from McDonald's.

I remember when burgerking used to have tacos :D omg those things were so greasy but so good!

Sonic. They are terrible.

Jack in the Box. Digusting Crap.

All of them are awful, there not good for you and you won't get anything good out of them.  I myself try to eat healthy and not get sucked into the propaganda of "healthy" fast food places.  I don't see a point in eating that shit, when you know that it won't get you any more healthier then what you are.  In fact it will make you much worse then what you are.

Burger King. Overpriced crap.

Probably McDonald's, though once a year I get a massive craving for a Mickey D's cheeseburger combo.

I find a double cheeseburger from McDicks usually does the trick, so I don't consider them bad. Burger King on the other hand... I haven't had a good burger there yet and I've tried nearly everything.
 
Wendy's is God Tier though.

The only burger I had in America that I didn't like was a Sonic's so I'll go for that.

Not sure if this still exists but the McDonald's hamburger, which is just bun, burger, bun. You can't have a burger with no accessories!! Gimme some tomatoes and cheese and good mayonnaise or something, jeez!! Then again, pretty everything at McDonald's sucks now.

A&W's. Ew.
 
However, I'm from Canada and I understand the A&W's here are different than anywhere else...