Estimate your router's real-world coverage after wall interference, and how many access points your home may need for full coverage.
A router's advertised range assumes open air with no obstacles. Interior walls, floors, and furniture each reduce signal strength — a common rule of thumb is roughly a 20% reduction in effective range per wall the signal must pass through.
Effective Range = Open-Air Range × (0.8 ^ Number of Walls)
Coverage Area = π × Effective Range²
Access Points Needed = Home Area ÷ Coverage Area (rounded up)
Enter your router's open-air range rating (check the manufacturer's spec sheet), the number of interior walls between the router and the farthest room you use Wi-Fi in, and your home's total square footage. The calculator estimates how much of your home a single router realistically covers and whether you'd benefit from a mesh system or extra access point.
A router rated for 100 ft in open air, placed where the signal must pass through 2 interior walls, has an effective range of about 64 ft — covering roughly 12,868 sq ft in theory. For a 2,000 sq ft home, that's more than enough on paper, but real-world layout, floors, and interference mean a mesh add-on is still worth considering for dead zones.
Considering router power/frequency band and typical obstruction factors.
Building materials absorb and reflect radio waves to varying degrees.
Yes — lower bands travel farther and penetrate obstacles better than higher bands.