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Asus RT-AC66U 802.11ac Dual Band Router review

Our Rating :
Price when reviewed : £173
inc VAT

Decent 802.11ac performance and built-in print server make this a great router


802.11n dual band, 4x 10/100/1000Mbit/s Ethernet ports

The Asus RT-AC66U is an 802.11ac dual-band Gigabit Ethernet router that provides extremely high-speed data. It also has two USB ports, so you can connect and share printers and external hard drives.

The unit itself is typically Asus in design, looking the same as all the other Asus routers we’ve seen. This is no bad thing because it’s a pretty stylish and slim unit that won’t look too conspicuous in your living room, although it does have three upgradeable antenna popping out of it. The RT-AC66U’s also pretty informative at a glance, having a line of easily seen and recognisable icons along its front lip. Blue LEDs illuminate to indicate data transfer over wireless or Gigabit Ethernet, and even though they’re bright, the LEDs don’t obscure the icons.

Asus RT-AC66U 802.11ac Dual Band Router

Of course, the most important thing about the RT-AC66U is its performance, and like other 802.11ac routers we’ve seen, it didn’t disappoint. Because of the scarcity of 802.11ac USB Wi-Fi dongles, we had to connect our test laptop to a Buffalo WLI-H4-D1300 802.11ac media bridge instead.

When we connected our test laptop to the RT-AC66U via 802.11ac, we achieved data transfer speeds of 209.7Mbit/s at one and 10 metres, and a highly impressive 126.5Mbit/s at 25 metres. For those of us still accustomed to a basic 802.11n Wi-Fi connection on the 2.4GHz band, these data transfer speeds appear lightning fast, but they pale in comparison to those achieved by the Ultimate award-winning Netgear R6300. Netgear’s router provided truly phenomenal transfer rates of 279.6Mbit/s at one metre, 288.9Mbit/s at 10 metres and a mind-blowing 195.7Mbit/s at 25 metres.

However, the RT-AC66U’s transfer speeds are very similar Buffalo WZR-1800H 802.11ac router. That router managed data rates of 209.7Mbit/s at one and 10 metres, and 104.8 Mbit/s at 25 metres.

One benefit of 802.11ac is improved Wi-Fi range, as is borne out by the transfer speeds detailed, but thanks to 802.11ac’s use of the 5GHz band, you can still benefit from increased range if you use 802.11n devices in the 5GHz band.

When we connected to the RT-AC66U via our Centrino’s built-in 802.11n Wi-Fi adaptor on the 5GHz band, we achieved data transfer speeds of 70.8Mbit/s at one metre, 93.2Mbit/s at 10 metres and 47.6Mbit/s at 25 metres. This is plenty fast enough to stream HD content to your device, and even though 47.6Mbit/s is nowhere as quick as 126.5Mbit/s, it’s still more than twice as fast as we typically achieve with a regular dual band 802.11n router. This means that even if you don’t have any 802.11ac-enabled devices yet, you can still benefit from a speed increase if you use the 5GHz band.

Asus RT-AC66U 802.11ac Dual Band Router

Sadly, its performance on the 2.4GHz band is more pedestrian, with us achieving data transfer speeds of 28Mbit/s at one metre, 29.6Mbit/s at 10 metres and 18.9Mbit/s at 25 metres when we used our Centrino’s built-in Wi-Fi adaptor. These transfer speeds are in keeping with the 2.4GHz band performance of the Netgear R6300 and Buffalo WZR-1800H routers. Once again, the Netgear R6300 is the faster router, transferring data at 24.7Mbit/s at 25 metres.

The RT-AC66U’s data transfer speed of 18.9Mbit/s is still quicker than 802.11n routers at 25 metres on the 2.4GHz band, and we were able to view Full HD video from an attached USB drive at 25 metres, which is absolutely amazing. This is an almost unheard of level of performance at 25 metres on the 2.4GHz band, and makes the RT-AC66U perfect for media fans whether they’re using the 2.4GHz or 5GHz bands.

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Basic Specifications

Rating *****
Modem type none
802.11b support yes
802.11g support yes
Draft 802.11n support yes
Draft 802.11n 5GHz support yes
Turbo mode none
Stated speed 1,300Mbit/s


WPA2 yes
Firewall yes
MAC address filtering no
DMZ yes


Size 36x207x149
Antennas 3
Internal/external antennas external
Upgradeable antenna yes
Number of WAN ports 1
Ethernet ports 4
Ethernet connection speed 10/100/1000Mbit/s
Other ports 2x USB
Wall mountable yes
Power consumption on 10W

Other Features

Dynamic DNS yes
Universal Plug and Play support yes
DHCP server yes
MAC spoofing yes
Port forwarding yes
WDS Support no
USB device support yes
QoS yes

Buying Information

Price £173
Warranty three years RTB