2.4 GHz or 5 GHz Wi-Fi: which band should you use?

By The SpeedFibre team, updated . 3 min read.

2.4 GHz or 5 GHz Wi-Fi: which band should you use?
In short 2.4 GHz goes through walls better but is slow and crowded. 5 GHz is much faster and less disturbed but reaches less far. Use 5 GHz when you are within a room or two of the router, and keep 2.4 GHz for smart devices and distant rooms.
Contents
  1. The two bands at a glance
  2. Why 2.4 GHz is often slow
  3. Why 5 GHz is faster
  4. Same name or two names?
  5. The test to run
  6. What about 6 GHz?

Your router usually broadcasts two Wi-Fi networks, sometimes under the same name. Choosing the right band can multiply your speed without spending anything.

The two bands at a glance

Criterion2.4 GHz5 GHz
RangeLongerShorter
Through wallsBetterWeaker
Possible speedLimitedHigh
Crowding in apartment buildingsVery highLower
Non-overlapping channelsFewMany
Interference (microwave, Bluetooth)FrequentRare

Why 2.4 GHz is often slow

The 2.4 GHz band is narrow: only three channels do not overlap. In apartment buildings, dozens of networks share them, plus microwaves and Bluetooth devices. The result: speed that often tops out at a few tens of Mbps, even on 500 Mbps fibre.

Why 5 GHz is faster

More channels, wider channels, less interference: 5 GHz allows several hundred Mbps near the router. Its weakness is range: behind two concrete walls the signal can become too weak and the device falls back to 2.4 GHz.

Same name or two names?

  • Same name (band steering): the router chooses for you. Convenient, but some devices stick to 2.4 GHz.
  • Two separate names (for example "Home" and "Home-5G"): you stay in control. Connect the TV, computer and nearby phones to 5 GHz and smart devices to 2.4 GHz.

Measure your connection now. Start the test

The test to run

  1. Connect your phone to the 5 GHz network and test 2 metres from the router.
  2. Run the same test on 2.4 GHz.
  3. Repeat in the room where you use the internet most.

Within minutes you will know which band is best in each spot. If neither is enough in distant rooms, the answer is Mesh or a wired access point: see extender, Mesh or powerline.

What about 6 GHz?

Wi-Fi 6E and Wi-Fi 7 add a 6 GHz band that is even faster and less crowded, with an even shorter range. It only helps with compatible devices. See Wi-Fi 6 and Wi-Fi 7.

#WiFi#WiFiDiagnosis#Ping

Sources and further reading

Frequently asked questions

Why can't my phone see the 5 GHz network?

Very old phones do not support 5 GHz. Also check that 5 GHz is enabled in the router interface.

Is 5 GHz dangerous?

No. Wi-Fi transmit power is low and regulated, whatever the band.

Which band for a camera or smart plug?

Most smart devices only work on 2.4 GHz, so keep that band on.

The SpeedFibre team Guides written and reviewed by a telecom engineer specialised in fibre optics (FTTH), with more than 8 years of hands-on network maintenance and measurement. Editorial policy.

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