Shopify says it has limit of filters for collections less than 5K products.
However, I see this shopify site with 25000+ products and still able to have default filter functionality. Can you advise how this site is able to accompish filter functionality. Many thanks
It’s not default filter functionality. It’s an app called Searchspring.
Hello there @reddyinc!
You can split products into smaller collections, but that gets hard to manage quickly and doesn’t scale well. If you’re dealing with very large collections, Shopify’s native filters usually won’t be enough. A dedicated search and filter app is the most practical and stable solution.
So I checked the website’s code using the browser’s inspector tool and discovered that they’re using Searchspring for filtering. It supports catalogs with 25,000+ products by indexing everything externally, which keeps search and filters fast. It also gives you strong control over facets, sorting, and merchandising rules.
Other solid alternatives that work the same way (external indexing) are Searchanise and Boost AI Search & Filter. Both are built for large catalogs and stay fast even as your product count grows.
If this helped, feel free to like the reply or mark it as the solution 
Just my 2cents:
Searchspring is flexible and fast, but
Hi,
Hope this will help
The 5000 products limit applies specifically to native Shopify automated collections. Large stores bypass this by using third-party search or filter apps which process data on external servers or by utilizing manual collections and custom storefront API integrations to handle the heavy lifting.