how long does fresh salsa last

I agree with Susan W. But you can always use it to cook with after it has become softer and less appealing to eat raw.

I'm assuming it's salsa you made with the usual ingredients of tomatoes, onion, lime? The acids will start breaking things down so there will be a decline in freshness and texture after a day or two, but if it's stored properly in the fridge, I'd still use it for at least a few days after that. It's going to get mushier as each day passes.