MacBook Pro has unexpectedly low Wi-Fi speeds

Wi-Fi Radio Signals from your Router fall off as the cube of the distance. Provided you are close to your Router and have clear line of sight and no competition from neighbors' Routers or known interference producers like microwave ovens.

All others need to do a more careful analysis to find out what is happening.

Wireless diagnostics:

Hold down the Option key while you click on the Wi-Fi icon on the menubar to open up the tools for investigating and fixing Wi-Fi issues

Choose "Open Wireless diagnostics", which opens the wireless diagnostics Assistant, but does not proceed.

NB> Wireless Diagnostics is an App that puts up its own MenuBar.

Using its Window menu, there are about eight different things you can do from here, but the top-level is to choose Diagnostics off the Window menu, or simply click (Continue) to do a quick check for Gross misconfiguration or operating problems. Your Admin password will be required. If any recommendations are shown, you should consider then seriously.

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Next is to hold down the Option key and click the Wi-Fi icon as before. The screen that opens shows operating parameters of your Wi-Fi network. There is a great deal, of valuable information in those numbers.

Readers are eager to interpret what is going on from the values there. Please Screenshot, transcribe, or photograph the results and post back in a reply on the forums. Looks like this older one.

"[...]I am curious whether there is anything I should look into, configuration-wise, that may be impairing my Wi-Fi speed? Thank you in advance for any comments or solutions."

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Single-Out this User:

Create a new Administrator user. See if you get the same error. If so, then it is an issue with this current user --and not the entire macOS.

if it make you queasy to share all, then feel free to Omit IP address, Router address, and BSSID. They are not needed for this analysis.

Then transcribe the settings that do not include any identifying numbers.

Your RSSI signal level is adequate at -52 dB, where -40 is typical right next to your Router, and -75 is unusably bad.

Noise at -91 dB levels, is not usually a concern.

You have made a nominal 80 MHz-wide connection using 802.11ax rules in the 5GHz band on channel 100.

using both of your two antennas, each is contributing 408 to your total of 816 M bits/sec. You are using modulation consisting of 256 different patterns.

if your connection were to drop down one step due to problems such as interference, you would still get 340 for each of your two antennas for a total of 680, and use a simpler modualtion with only 64 patterns, which should be Much more stable.

Without the names of your devices, I can not tell whether you have connected to the extender or the main Router. But I would expect an extender would be closer and provide better results, if you have placed them appropriately.

The fastest possible speeds you can likely attain is about 1134 M bits/sec, and that would require Very strong signals, such as right next to your Router (or extender)

I see no trace of the 250 you were lamenting.

¿How are these numbers falling short of your expectations?

.. most important are:

RSSI (signal strength) and

Noise