Asus RT-AC51U dual-band router - everything you need to know

Everything you need to know about the budget Asus RT-AC51U dual-band router - features, specifications, price info, problems, set up and documentation, quick test and review

Asus RT-AC51U router review
Asus RT-AC51U dual-band router 
Asus RT-AC51U dual-band router, that is the product I will be checking with you today. That is one of the cheaper dual-band routers offered by Asus, offered at just $50. In this short review we will take a closer look at this Wireless-AC750 router main features, specifications as well as the most common problems that may occur with it.
Asus RT-AC51U - the basics:
  • 802.11ac dual-band wireless at up to 733 Mbps for high-performance wireless
  • Expanded wireless coverage with two fixed high-gain antennas
  • USB port for printer networking, storage sharing, or 3G/4G connections
  • ASUS AiCloud app to access, sync, share and stream your files on the go –quickly and easily
  • Easy 30 second setup and robust controls like network monitoring through ASUSWRT dashboard
Asus RT-AC51U dual-band router tested
Asus RT-AC51U main features and specifications:
Network Standard: IEEE 802.11a, IEEE 802.11b, IEEE 802.11g, IEEE 802.11n, IEEE 802.11ac, IPv4, IPv6
Product Segment: AC750 complete AC performance : 300+433 Mbps
Coverage: Small and medium homes

Data Rate
  • 802.11a : 6,9,12,18,24,36,48,54 Mbps
  • 802.11b : 1, 2, 5.5, 11 Mbps
  • 802.11g : 6,9,12,18,24,36,48,54 Mbps
  • 802.11n : up to 300 Mbps
  • 802.11ac : up to 433 Mbps
  • External 5 dBi antenna x 2
  • Internal PCB antenna x 1
  • Transmit/Receive
  • MIMO technology
  • 2.4 GHz 2 x 2
  • 5 GHz 1 x 1
  • 8 MB Flash
  • 64 MB RAM
Operating Frequency: 2.4 GHz / 5 GHz
Encryption: 64-bit WEP, 128-bit WEP, WPA2-PSK, WPA-PSK, WPA-Enterprise , WPA2-Enterprise, Radius with 802.1x, WPS support
Firewall & Access Control
  • Firewall: SPI intrusion detection
  • Access control: Guest access, Parental control, Network service filter, URL/Port filter
  • VPN Support
  • PPTP server
  • OpenVPN server
  • PPTP client
  • L2TP client
  • OpenVPN client
  • WAN Connection Type
  • Internet connection type : Automatic IP, Static IP, PPPoE(MPPE supported), PPTP, L2TP
  • Dual Link support 
  • Multicast Proxy support
Ports: RJ45 for 10/100 BaseT for WAN x 1, RJ45 for 10/100 BaseT for LAN x 4
USB 2.0 x 1
Asus RT-AC51U dual-band router specs
Asus RT-AC51U specifications
Other features
- User definable rules for IP/MAC/Port
- Upload and download bandwidth management
- ACK/SYN/FIN/RST/ICMP with highest priority
Parental Control
Guest Network : 2.4 GHz x 3, 5 GHz x 3
Enhanced media server (AiPlayer app compatible)
- Image : Jpeg
- Audio : mp3, wma, wav, pcm, mp4, lpcm, ogg
- Video : asf, avi, divx, mpeg, mpg, ts, vob, wmv, mkv, mov 
AiCloud personal cloud service
3G/4G data sharing
Printer Server
- Multifunctional printer support (Windows only)
- LPR protocol support
Download Master
- Support bt, nzb, http, ed2k
- Support encryption, DHT, PEX and magnet link
- Upload and download bandwidth control
- Download scheduling
AiDisk file server: Samba and FTP server with account management
  • IPTV support
  • Button
  • WPS Button, Reset Button, Power Button
  • LED Indicator
  • USB x 1
  • LAN x 1
  • Wi-Fi x 1
  • WAN x 1
  • Power x 1
  • Power Supply
  • AC Input : 110V~240V(50~60Hz)
  • DC Output : 12 V with max. 1 A current
OS Support
  • Windows® 10 
  • Windows® 8.1 
  • Windows® 8 , 32bit/64bit
  • Windows® 7 , 32bit/64bit 
  • Windows® Vista , 32bit/64bit
  • Windows® 2000 
  • Windows® XP , 32bit/64bit
  • Windows® Server 2003
  • Windows® Server 2008
  • Mac OS X 10.1
  • Mac OS X 10.4
  • Mac OS X 10.5
  • Mac OS X 10.6
  • Mac OS X 10.7
  • Mac OS X 10.8
  • Mac OS X 
  • Linux Kernel (Support Ubuntu only)
  • Linux
  • AndroidTM
Dimensions: 189 x 129 x 36 ~ mm (WxDxH) 
Package content
.RT-AC51U Wireless-AC750 Cloud Router
.RJ-45 Cable
.Power Adapter
.Quick Start Guide
.Warranty Card
.Support CD (User manual & Utility software)
Operation mode: Wireless router mode /  Access point mode

User experience and problems

Couple of years ago I bought the ASUS RT-N12E Wireless-N300 router and used it for couple of months. Honestly, it was doing a pretty good job,especially for the price I got it back then - around $45, very cheap. Since I upgraded on the ISP I rely mostly on their stock routers which are usually Huawei and most of them had issues. For example couple of months I bought a Chromecast and there was no way to run it with the router I had.

I didn't succeed with the ASUS RT-N12E Wireless-N300 as well. As far as we are speaking about the Asus RT-AC51U I think the user experience got a bit better with this newer model. 

ASUS RT-N12E Wireless-N300 router - our opinion

Here is how Asus promote their product:
  • "ASUS RT-AC51U Dual-band Wireless-AC750 router gives you both fast wireless speed and great value to upgrade your home network to the latest 802.11ac Wi-Fi technology today. Experience simultaneous dual-band connectivity and enjoy 300 Mbps speed on the 2.4 GHz frequency and up to 433 Mbps in 5 GHz band. 
Thanks to its multipurpose USB port, RT-AC51U is much more than just a router. Plug in a USB hard disk drive and you’ve got an instant file server — and one that extends into the cloud via ASUS AiCloud. Alternatively, attach a USB printer to RT-AC51U to create a print server for sharing one device with several users. The USB even accommodates 3G/4G mobile broadband dongles for two broadband (WAN) connections on one router so you’ll never again have to worry about your internet access going down. The port can even be used for powering gadgets such as smartphones and tablets, making it a handy charging station. 

The easy-to-use ASUSWRT graphical user interface unlocks the power of RT-AC51U giving robust control to optimize your network for you. 30-second setup and easy traffic management means even network newbies can enjoy its sophisticated features, while power users will love its IPv6 support, multiple wireless SSIDs and encrypted VPN access.
  • Delivering 2.4GHz and 5GHz concurrent bands at up to 300Mbps and 433Mbps, respectively, RT-AC51U has a total combined bandwidth of up to 733Mbps. Perform basic tasks like Web browsing and file downloading on the 2.4GHz band, while simultaneously allowing multiple devices to stream in Full HD or support online gaming and other bandwidth-demanding applications smoothly on the clearer 5GHz band.
  • Powered by 5th generation Wi-Fi (5G Wi-Fi), the 802.11ac chipset gives the RT-AC51U faster wireless speeds than N technology. At 2.4 GHz, it reaches 300 Mbps, while on the 5GHz band it blazes to 433 Mbps. The upgraded bandwidth has the higher capacity you need to increase Wi-Fi enjoyment at home. With notebooks, desktops, pads, and smartphones now all Wi-Fi-reliant, it’s time to upgrade to the next generation to expand you connectivity now and in the future."
And if you are new to our site I would suggest you to check our full list of consumer product reviews here.

Asus RT-AC51U - our verdict
If you are looking for an affordable Wireless-AC750 router I think the Asus RT-AC51U is a great choice, especially if you manage to find it on good Black Friday deal these days. My impressions with Asus products are pretty good these days, they make affordable, stable and relatively easy to use products that are quite reliable in most cases. 

Top 5 routers - 2018 buying guide

Thank you for checking my Asus RT-AC51U review!