What is Child max weight?

Child max weight is the heaviest child a car seat is approved to carry, given in kilograms. It matters because a seat is tested and approved for a set weight, so a child over the stated maximum is outside what the shell, harness and structure are rated for, however well it seems to fit.

The ceilings here are far apart. AXKID lists 50, the highest of the group, and Baby Trend lists 45.36. Baby Plus lists 36. Baby Jogger lists 29.48 and BeSafe lists 22, so those suit a lighter child. A heavier child narrows your choices, so read this before you weigh the other features.