What is the 20 60 20 rule in photography?
It is a framing guide. Roughly 20 percent of the frame goes to the background, 60 percent to the subject, and 20 percent to the foreground or breathing room.
The rule is a starting point for composition rather than a law. The idea is that giving the subject around sixty percent of the frame keeps it dominant, while the remaining space above and below stops the shot feeling cramped and gives you room to crop later.
It gets quoted a lot in photography forums, and it is genuinely useful when you are learning to frame. It is far less useful once you are shooting for a specific place the image has to live.
For ecommerce, the platform decides your framing, not a rule of thumb. Amazon wants the product filling at least 85 percent of the frame on the main image, which is nothing like a 20 60 20 split. A lifestyle image for a website hero might need a lot of empty space for text to sit in. A social crop is square or vertical and throws away the sides of whatever you shot.
So the practical version is this. Learn the rule, then let the destination override it. We shoot to the crop the image is going to be used in, which usually means shooting wider than the final frame so the same product works across a listing, a website and an ad without a reshoot.