Shop for garage shelving for ten minutes and you will see the same unit sold at wildly different capacities. The steel has not changed. The way the number is quoted has.
Per shelf, not per unit
This is the single biggest source of confusion. A "3,000 lb" five-tier rack usually means 600 lbs per shelf, multiplied by five. A rack quoted at 7,200 lbs is often 1,800 lbs per shelf across four shelves. Neither number tells you what one shelf will hold until you divide. When you compare two racks, always convert both to per-shelf capacity first — it is the only figure you will actually use when you set something down.
Evenly distributed means evenly distributed
Ratings assume the load spreads across the whole shelf on a solid deck. A single engine block in the center of a wire shelf is a completely different load case from twelve evenly spaced paint cans of the same total weight. If you plan to store dense, concentrated items, add a plywood deck on top of the wire — it spreads the point load into the frame and stops small items from tipping through.
Boltless is fine. Boltless and unanchored is not
Rivet or boltless shelving goes up fast and holds its rating perfectly well. What it does not do is resist being pulled forward. Any unit taller than about five feet should be anchored to the wall, and that goes double if the shelves are loaded top-heavy or if there are children in the house. One bracket and two screws into a stud is the cheapest insurance in the garage.
Depth costs you more than you think
An 24-inch deep shelf holds more than an 18-inch shelf, and it also hides things. Anything pushed to the back of a deep shelf is functionally gone. For most garages, 18 inches deep at chest height and 24 inches deep down low — where you can crouch and see in — beats deep shelving everywhere.
Adjustable beats permanent
Whatever you store today, you will store something else in two years. Racks with adjustable beam heights let you re-space for a tall item instead of buying another unit. It is a small premium at purchase and the reason a rack lasts a decade rather than a season.
When you are ready to compare specific units, our shelving that holds weight is grouped by build rather than by price, and the workbench and tool storage is where the heavy, frequently-used things belong.