Websites and speed

Video calls stutter or freeze on a Mac

Calls need steady latency and steady upload more than high speed. Short latency spikes, packet loss and background uploads cause most freezes.

Applies to: All current macOS versions. networkQuality needs macOS 12 Monterey or later.Checked: 29 October 2026

Symptoms

Short latency spikes. Spikes of a few hundred milliseconds freeze video. An average latency value does not show them.
Packet loss. Lost packets break audio, even on a fast connection.
Background uploads. A backup or sync that fills the upload link delays your video.
Bufferbloat. Latency rises when the network is busy.
A weak Wi-Fi link. Distance and interference cause both loss and spikes.

Ping your router for one minute. Look for single times that are much higher than the others.
```
ping -c 60 192.168.1.1
```
Find the router address first, if you do not know it. It is the gateway line.
```
route -n get default
```
Ping a server on the internet for one minute.
```
ping -c 60 1.1.1.1
```
Look for uploads in Activity Monitor > Network, or with nettop. See Find which app uses your bandwidth on a Mac.
Measure responsiveness. Do this before the call, not during it.
```
networkQuality
```

Pause cloud sync and backups during calls.
Move closer to the router, or connect with an Ethernet cable.
If Bluetooth headphones share 2.4 GHz with your Wi-Fi, use a 5 GHz network. See Bluetooth headphones and Wi-Fi interference on a Mac.
If spikes repeat at a regular interval, read AirDrop, AWDL and latency spikes in games and calls.
If latency rises when the network is busy, read Bufferbloat: calls lag when the network is busy.
If loss or spikes are past the router, turn off video and use audio only.

Kilobat's stutter test pings the router every 50 ms for 20 seconds. It shows each spike, and whether spikes repeat at a regular interval.
```
kilobat stutter
```
To test the internet path instead of the router, add a target.
```
kilobat stutter --target internet
```
kilobat diagnose reports latency, jitter and loss. Kilobat warns about calls above 300 ms latency, 30 ms jitter or 2% loss.
To test whether AirDrop and AWDL cause the spikes, pause them. macOS asks for an administrator password.
```
kilobat low-latency on --for 1h
```
Needs an administrator password.
The stutter test is free in the Health tab. Compare with low-latency on needs Pro. See Test for call stutter.

Why do calls stutter when the speed test is fast?

A speed test averages its measurements. Short spikes and small amounts of loss disappear in the average, but they freeze calls.

Should I run a speed test during a call?

No. The test fills the link and makes the call worse while it runs.

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