The cheapest routers-which cost as little as $20 or $30-use a single band, or frequency, of the Wi-Fi standard that came out in 2009 (802.11n, rarely referred to as Wi-Fi 4). Current-generation technology: Since we’re looking to improve your Wi-Fi, we considered only dual- or tri-band routers that support the more recent Wi-Fi 5 and Wi-Fi 6 standards.