12.6 Megabits per second (note bits not bytes) is somewhat slow for modern Wifi. But it varies depending on what standard, quality of signal (also consider interference), and how many devices are on the WLAN.
Note of course the connection between device and AP is limited to the capability of whichever is lower specced.
The wiki article has a table of expected top speeds https://en.wikipedia...802.11#Protocol
Also note with the earlier standards (before 802.11n) the entire bandwidth is divided among devices including the AP, and including upstream/downstream.
Whether your connection could be considered "good" - you'd need to compare it to a best case scenario given your current network topology.
If you have an Android device, Wifi Analyser is a handy tool. It can give a graph of available networks and has a channel view mode so you can see any overlap/contention that might be going on.
Edited by Rybags, 30 April 2016 - 12:49 PM.