Guide · Slow internet

Slow internet on your Mac? How to test the speed and find what slows it down

By the AI Repair team · Updated 20 October 2026

When web pages crawl and video keeps stopping to load, the first question is where the slowness is: in your Mac, in the Wi-Fi between your Mac and the router, or in the internet line itself. A speed test answers most of that in a minute. This guide shows how to test, what the numbers mean, and what to do about each cause.

In short

Test the speed, ideally twice: once where you usually sit and once next to the router. If it’s fast next to the router but slow where you sit, the Wi-Fi is the problem: move closer, or move the router. If it’s slow everywhere, restart the router and modem, pause big downloads and backups, and turn off any VPN. If it’s still slower than the plan you pay for, call your internet provider with your results.

1. Test your internet speed

The simplest test is your internet provider’s own, in your web browser:

Open your web browser, such as Safari.
Search for your provider’s name and the words speed test, and open the test on the provider’s own website.
Click its start button, and wait until it shows your download and upload speed, usually in Mbps (megabits per second).

Any speed test uses data, a few hundred megabytes on a fast line, which matters on a phone’s hotspot or a plan with a data limit. Run it when nothing else is downloading, and try it at a few different times of day: a line that slows every evening is busy, not broken.

macOS 12 Monterey and later also have a test of their own, which only measures and changes nothing on your Mac (Apple’s guide). If you’re happy to type one command: press ⌘ Space, type Terminal and press Return, then type networkQuality -s and press Return. After about a minute, Downlink capacity is your download speed and Uplink capacity your upload speed (on macOS 12, Download capacity and Upload capacity). Type the -s too: it tests one direction at a time, as AI Repair does, and without it the download can read much lower than it really is.

2. What the results mean

Download speed is how fast things reach you: web pages, films, updates. Streaming services ask for about 5 Mbps for Full HD and about 15 to 25 Mbps for 4K.
Upload speed is how fast you send: your picture in a video call, photos, backups. A video call works from about 1 Mbps each way, and looks its best with about 4 down and 2.5 up.
The delay, which speed tests call ping, latency or responsiveness, is how quickly the line answers. It matters more than speed for calls and games: macOS’s test rates responsiveness Low, Medium or High, and Apple says that with Low, FaceTime calls or games may be unreliable while other devices download or upload.

Compare the download speed with the plan you pay for. Plans are sold as “up to” a speed, and Wi-Fi rarely reaches the full figure, but results far below it in several tests, even next to the router, are worth a call to your provider.

3. Find out whether it’s the Wi-Fi or the line

Run the test again with your Mac close to the router, or, best of all, connected to it with a network cable. Then compare:

Fast close to the router, slow where you sit: the Wi-Fi is the weak part. Walls, floors and distance all cost speed. See step 6.
Slow everywhere, even on a cable: the line or the router is the problem. Restart the router (step 4), then call your provider if it stays slow.
Slow only on your Mac, while a phone or another computer is fast in the same spot: look at what your Mac is doing (step 5) and at its Wi-Fi settings, and restart your Mac.

4. Restart the router and modem

Unplug the router and the modem (often one box from your provider), wait about a minute, then plug them back in. They can take several minutes to start up fully. When your Mac is online again, test once more.

5. Pause what’s using the internet

Everything on your network shares one line. A film streaming on the TV, a game downloading, photos uploading to iCloud or a backup to the cloud can each take most of it.

Pause big downloads and uploads on your other devices, then test again.
On your Mac, open Activity Monitor (press ⌘ Space and type its name) and click Network: apps that send or receive the most data are at the top when you click the Sent Bytes or Rcvd Bytes column.
Turn off any VPN and test again. A VPN sends everything through another company’s servers, which can slow it down.

6. Get a better Wi-Fi signal

Move closer to the router, or put the router somewhere central and in the open, not in a cupboard or behind the TV.
Check the Wi-Fi menu. Click the Wi-Fi icon in the menu bar: macOS shows a warning such as Weak Signal there, and may offer Wi-Fi Recommendations when it spots a problem.
Keep USB 3 devices and cables away from your Mac where you can: Apple notes they can interfere with Wi-Fi.
One name for all the router’s bands. Apple recommends one network name for every band, so your Mac can choose the best one, and keeping the router’s firmware up to date (Apple’s router advice). The router’s maker or your provider can help with both.

7. Update and restart your Mac

Install any waiting updates in System Settings › General › Software Update (System Preferences › Software Update on macOS 12): Apple fixes Wi-Fi problems in updates. Then restart your Mac, which also starts its connection to the router fresh.

8. When to call your internet provider

If the speed stays far below your plan after you’ve restarted the router, even with your Mac on a cable or right next to the router, the problem is on the line, and only your provider can fix it. Tell them your test results and the times you ran them. They can test the line from their side, and replace an old router.

Advice you can skip

Changing DNS servers to speed up downloads. DNS turns names like apple.com into addresses; it doesn’t change how fast a film or a file downloads.
Buying an “internet booster” app. No app on your Mac makes the line itself faster.
Resetting your Mac’s network settings for a slow connection. It’s a last resort for a connection that doesn’t work at all, and it needs a restart.
Testing over and over. Each test uses data and briefly fills the line; a few tests at different times tell you more.

Let AI Repair measure it

Type “my internet is slow” and AI Repair runs macOS’s own test for you: the download and upload speed, the delay while the line is quiet and while it’s busy, how steady it is, and whether anything gets lost on the way. Then it tells you in plain words what your line is good for: streaming films and TV, video calls and online games.

It checks your Wi-Fi too: the signal, how crowded your channel is, and whether your Mac is on the slower band when the faster one is in reach
Then it fixes gentlest first: turning Wi-Fi off and on, or joining a stronger network your Mac already knows, and it shows you how to restart your router
It measures again after a fix, so you can see what changed, and tells you plainly when only your provider can make the line faster

The test takes about 20 seconds, up to a minute on a slow line or an older version of macOS, and uses some data: AI Repair tells you before it runs. Each change waits for your OK unless you’ve set that kind of fix to Auto.

Download for Mac

Asking and checking are free · Apple silicon, macOS 12 or later

Common questions

How fast should my internet be for streaming and video calls?

About 5 Mbps download for Full HD films and 15 to 25 Mbps for 4K. A video call works from about 1 Mbps each way and looks best with about 4 down and 2.5 up. Several people streaming at once need that much each.

Why is my internet slow only on my Mac?

If other devices are fast in the same spot, look at your Mac: a VPN, an app downloading or backing up in the background, a weak Wi-Fi signal where the Mac sits, or a Mac that needs a restart or an update.

Is Wi-Fi slower than a cable?

Usually, yes. Wi-Fi loses speed with distance, walls and other networks nearby, while a network cable gets the line’s full speed. That’s why a test on a cable tells you what your line can really do.

Does a VPN slow down my internet?

It can. Everything you send and receive goes through the VPN company’s servers, which adds distance and can cap your speed. Turn it off and test again to see how much it costs you.