TP-Link Archer AX21 vs ASUS RT-AX55: Which Budget WiFi 6 Router Is Better?

Two budget WiFi 6 routers, similar price, similar specs on paper. So why does everyone keep asking which one to buy?

Because the difference that matters isn't in the throughput numbers.

Both the TP-Link Archer AX21 and the ASUS RT-AX55 deliver solid WiFi 6 performance for a small home or apartment.

The real decision is whether AiMesh expandability, the RT-AX55's ability to add a second node later, is worth paying a little more for now.

Coverage Performance

Both routers provide comparable coverage in smaller homes (under 1,500 sq ft). In a direct comparison in the same 1,200 sq ft apartment:

• 5GHz throughput at 15 feet: AX21 650 Mbps, RT-AX55 720 Mbps — both excellent
• 5GHz throughput at 50 feet through 2 walls: AX21 160 Mbps, RT-AX55 195 Mbps — marginal advantage to RT-AX55

Mesh: The Real Differentiator

The RT-AX55 supports AiMesh — you can add any compatible ASUS router as a second node and manage both from the same interface. If you later need to extend coverage, you buy a second ASUS router rather than replacing everything.

The AX21 has no mesh capability. If you need extended coverage, you start over.

App Quality

TP-Link Tether is simpler and more approachable. ASUS's app is more feature-rich but more complex. For users who want basic management, Tether wins. For users who want QoS, VPN, and advanced security features, ASUS wins.

The Verdict

Buy Archer AX21 if: small home or apartment, budget is tight, no plans to expand.

Buy RT-AX55 if: you may need to extend coverage later, you want AiProtection security features, or you are willing to pay a small premium for a more capable platform.

Related Guides

• TP-Link Archer AX21 Review - AX21 detailed review
• Best Budget WiFi Routers - all budget options
• Best Mesh WiFi Systems - when to go full mesh