Here you can rename your feed for easy identification if you are creating multiple feeds.
By default, the feed will include up to 1,000 items per feed page.
Your store may have more items so you can increase the number of items up to 100,000 items. The maximum number of items per feed page is 1000 products x 100 variants per product (Shopify’s limit) = 100,000 items.
An item is a single product or product variant in Shopify. Facebook identifies every product variant as an entirely separate product and so is classified as a separate item.
10 Shopify products each with 5 variants (eg T-shirt colors) would be a total of 50 items.
Due to technical constraints, Shopify has a limitation on the how big a single feed can be. Sometimes this can vary depending on the number of items and how much information is being passed (eg description length). Some stores will produce an error when trying to load their feed.
An error may be:
Request timed out
Liquid error: Memory limits exceeded
If this happens, the best solution is to decrease the number of items per page.