2.4 GHz or 5 GHz: which band for which room

Most routers broadcast two networks at once, on 2.4 GHz and on 5 GHz, and newer ones add 6 GHz. The usual advice is "use 5 GHz, it's faster". That's true where the 5 GHz signal is good. In a lot of homes, it isn't good everywhere.

The trade-off in one paragraph

2.4 GHz travels further and passes through walls and floors better, but it's slower and shared with neighbors' networks, Bluetooth, baby monitors and microwave ovens. 5 GHz is much faster and far less crowded, but it loses more with every wall. 6 GHz is faster still, cleaner still, and shorter-ranged still.

So the right band depends on where you are, not on which is better in general.

A rule of thumb by room

• The router's room and rooms next to it, with open doors: 5 GHz, or 6 GHz if you have it. There's no reason to use anything slower.
• One or two plasterboard walls away: usually still 5 GHz.
• Behind masonry, concrete or a floor away: test both. 5 GHz may still win, or it may be weak enough that it keeps breaking up, in which case 2.4 GHz gives a slower but steadier connection.
• Garden, garage, far bedroom behind two brick walls: often 2.4 GHz, or better, a node or access point closer to that area.

The key word is steady. A connection that is fast for ten seconds and then stalls feels worse than one that is moderately fast all the time.

How to test both bands in a room

Most routers merge both bands under one network name and choose for you. To compare, you can temporarily give them different names in the router settings (for example "Home" and "Home-5G"), connect to each one in the problem room, and see which behaves better over a few minutes. Afterwards you can merge them again.

Look at more than speed: how much the response time varies, and whether requests get lost. Those are what make calls, games and streams stutter.

Devices that decide for you

• Smart plugs, cameras, doorbells and many smart home gadgets only support 2.4 GHz. Far from the router they'll struggle no matter what your phone does.
• Phones and laptops switch between bands on their own, sometimes late. If your phone clings to 2.4 GHz next to the router, that's the device being cautious, not a fault.

If a far room is only usable on 2.4 GHz, that's often a sign the room needs coverage, not a setting. See Wi-Fi weak in one room and what walls do to the signal.

Map the bands, not just the house

The same room can look fine on one band and poor on the other. WiFi Heatmap measures how the connection behaves where you stand; connect to each band in turn, map the problem rooms, and you'll see where 5 GHz still holds and where it gives up.