No,it should not be kept ketchup in the fridge.Not just does it contain vinegar, yet tomatoes are normally acidic, and this assists with safeguarding the item in encompassing (room temperature) conditions."
Ketchup can be kept unrefrigerated for as long as one month however on the off chance that you don't think you'll complete the jug in that time period, it's ideal to keep it in the cooler.