Wi-Fi

Crowded Wi-Fi channels near your Mac

Networks on the same channel share the air time. In apartments and offices, many networks can share one channel and slow each other down.

Applies to: All current macOS versions. You change the channel in the router, not on the Mac.Checked: 29 October 2026

Symptoms

  • The signal is strong, but Wi-Fi is slow at busy times, such as evenings.
  • Many networks show in the Wi-Fi menu.
  • Speed changes much from minute to minute.

Likely causes

  • Many networks on one channel. Each network on the channel must wait for the others to stop sending.
  • Overlapping 2.4 GHz channels. Apple says that only channels 1, 6 and 11 do not overlap on 2.4 GHz.
  • Wide channels. Wide channels are faster, but they overlap with more neighbors. Apple says that smaller widths allow more channel reuse.

How to check

  1. Show the current channel, and the channel of each nearby network.

    system_profiler SPAirPortDataType | grep -E 'Channel|Signal / Noise'

    Output One Channel line for your network, then one for each network in Other Local Wi-Fi Networks.

  2. Count the strong networks on the same channel as yours.

  3. Hold the Option key and click the Wi-Fi icon. Make sure of your channel and band.

How to fix it

  1. Open the settings page or app of the router.

  2. Set the channel to Auto. Apple recommends this.

  3. If the router cannot select a channel itself, select a channel that nearby routers do not use.

  4. On 2.4 GHz, use channel 1, 6 or 11, with a width of 20 MHz.

  5. On 5 GHz and 6 GHz, set the width to Auto.

  6. Use 5 GHz or 6 GHz when you can. These bands have more channels.

With Kilobat

  1. Show the congestion of each channel in the current band, and the least crowded channel.

    kilobat channels

    Output The current channel, the recommended channel and a congestion score for each channel.

  2. List nearby networks with their channel, band and width.

    kilobat scan

  3. Channel crowding in the app is part of Kilobat Pro. The CLI is free.

Questions

Can the Mac change the channel?

No. The router selects the channel. The Mac follows the router.

Will the best channel stay the best?

No. Neighbors change their channels. Hidden interference can also change the best choice.

Sources

Sources checked on 29 October 2026. Man pages are the ones installed with macOS; open one with man <name> in Terminal.