How do I know if the strainer can fit my drain?

Sometimes, the product descriptions on the package or website are so confusing. It is saying that most sinks have a 3.5 inch – 4 inch diameter drain opening. But why the description of some strainers is 4.5 inch?

Bathtub Drain Strainers/filter Baskets Stainless Steel Hair - Temu

Signs You Have Blocked Drains No Probs Plumbing And Electrical

plumbing - How can I install the drain for my reverse osmosis water filter? - Home Improvement Stack Exchange

Best Bathroom Sink Basket Strainers to Prevent Clogs

Sink strainer options and what to consider

Best Kitchen Sink Strainer - OXO Silicone Sink Strainer Review

The Plumber's Choice 3-1/2 in. - 4 in. Kitchen Sink Spin and Seal Stainless Steel Drain Assembly with Strainer Basket - Threaded Stopper ESS1457 - The Home Depot

Water Draining Away From My Sink…

Highcraft Stainless Steel Kitchen Sink Spin and Seal Basket Strainer Replacement for Standard Drains (3-1/2 Inch) With Threaded Stopper…

Bathroom Sink Drain Strainer Stainless Steel, 2 Pack Floor Drain Filter Mesh Basket Filter Hair Trap Anti-Clog Slag Strainer - Large Wide Rim 2.16 Diameter

Frequent asked question for plumbing product

The Plumber's Choice 3-1/2 in. - 4 in. Kitchen Sink Spin and Seal Stainless Steel Drain Assembly with Strainer Basket - Threaded Stopper ESS1457 - The Home Depot

LKPDQ1CR

Mestream 2PCS Bathroom Sink Drain Strainers, for Diameter 1.3-1.6 (Depth Than 2) Drain Hole, Small Cylinder Porous Hair Catcher, Premium Stainless Steel Drainer Filter, (1.1)

Kitchen SinkShroom stainless steel sink strainer review