Walmart organizes products listed on their marketplace by UPC. You can find what UPC a specific product is using by inspecting the product page's source code. This is an advanced technique that allows you to find the most popular UPCs for your products.

3. On the source page press CTRL-F if you are on Windows or CMD-F if you are on Mac and search for 'upc'

4. Look for "upc": followed by a 12 digit number

**Disclaimer** 

Walmart does not make UPCs visible for ALL listings. This method provided by Listing Mirror is a tool to be used when made available by Walmart.com

If the UPC cannot be found with the above method, you will need to source another method to find UPCs.