[CommieBobDole]

I don't know how long it takes to go bad, but I do know that I use ketchup very rarely, mostly to make other sauces, and I keep a bottle in the fridge and check it before every time I use it. I've tasted ketchup that's been in the fridge for 2-3 years past the expiration date that has no obvious defects and looks and tastes just like fresh ketchup. I think the vinegar and the cold provide a lot of preservation.