Amazon's Prime Day is 4 days this year, and Walmart is fighting back with a week of deals of its own. How to score the best bargains this year.

The most popular stores, like Walmart and Target, are holding their own competitor sales during Prime Day. Here are all the sales to check out

In one corner is Amazon Prime Day. Amazon will run four days of sales, starting on July 8 and running through July 11. In the other corner is Walmart Deals. This event also starts on July 8 but, unlike Amazon, it will go through July 13, giving shoppers two extra days of deals.