The capacity of a multi-hop wireless network is the traffic payload that it can transport. This is a prominent quality of service issue, particularly in the highly constrained settings of 802.11 wireless mesh network. In this paper, we consider two complementary definitions of the capacity. A network-wise capacity is defined as the sum of the upload traffic, and a flow-wise capacity highlighting the unfairness among traffic flows. We study the behavior of these capacities face to several parameters: routing protocols, number and location of gateways bridging the network to the Internet, and the physical network topology. Thorough simulations highlight the insensitivity of the capacity face to these parameters while it is directly related to the congestion around the gateway. Furthermore, we show that if the number of gateways increases, the capacity tends to a maximum boundary.