There are three options when choosing a weight capacity based specifically on your needs; 600lb, 750lb, or 850lb weight capacity.
When choosing your capacity, ask yourself this question: who will be using the ramp? A mother or father utilizing a walker or wheelchair? Will someone have a stroller with them, or possibly a power scooter? If the person is in a wheelchair (non-powered) and must be pushed up, you must take into account the weight of the wheelchair, the weight of person in the wheelchair, and the weight of the person pushing them up the ramp. Having too much weight per axle could cause the ramp to buckle or crack.