What Is Jitter? Good Jitter Levels, Tests and Fixes

Jitter is how much your ping changes from one packet to the next, measured in milliseconds. A connection that answers in 20, 21 and 22 ms has low jitter; one that jumps between 20 and 90 ms has high jitter, even if the average looks fine. High jitter makes calls break up and games stutter. Our ping test measures it in a few seconds.

What is jitter?

Jitter is variation in the delay of packets as they arrive. Data leaves your device as an even stream, but congestion, queues and radio interference on the way can bunch some packets up and hold others back. Network standards call this packet delay variation. RFC 3393 avoids the word jitter because different groups use it in different ways, and that is worth remembering when two tools give you different numbers.

How is jitter measured?

There is more than one formula, so results from different tests are not directly comparable.

Our ping test and speed test take the average change between consecutive round trips. Pings of 20, 30 and 25 ms change by 10 and 5 ms, so the jitter is 7.5 ms.
Voice and video apps that use RTP follow RFC 3550, which defines interarrival jitter as a smoothed running average: each new difference moves the estimate one sixteenth of the way toward it.
The ping command on a Mac or Linux prints a standard deviation (stddev) at the end, which is another way of describing the spread.

What is a good jitter?

Lower is better, and for calls Microsoft publishes concrete limits for Teams that work as a yardstick for any voice or video app.

Jitter	What it means
Under 15 ms	Meets Microsoft's Teams target even for the provider's part of the path alone. Good for calls and games.
15 to 30 ms	Within Teams' end-to-end target from your device, Wi-Fi included. Usually fine.
Over 30 ms	Above Teams' target. Our ping test marks the connection as unstable, and calls may break up.

Microsoft's targets apply to any 15-second interval, so a short burst of high jitter in the middle of a call counts. For fast online games, steady matters as much as low: a constant 50 ms often feels better than a ping that swings between 20 and 80.

Why does jitter make calls and games stutter?

Call apps hold incoming audio in a jitter buffer, which Cisco's documentation calls a playout delay buffer, and play it out at a steady pace. A packet that arrives after its turn has passed is thrown away, and you hear a dropout. Most buffers adapt, growing when jitter rises, but a bigger buffer adds delay, so high jitter costs you either gaps or lag. Games have no buffer to hide behind. A late update shows up as stutter or players jumping around.

How to test your jitter

Run our ping test. It sends 25 checks to the nearest Cloudflare data center and reports average ping, best, worst, jitter and packet loss.
Run the speed test to see jitter alongside download, upload and latency under load.
For a longer sample, run ping -c 100 1.1.1.1 on Mac or Linux and read the stddev, or ping -n 100 1.1.1.1 on Windows and compare the minimum and maximum.
Test once on a cable and once on Wi-Fi, and repeat at the time of day your calls break up.

What causes jitter?

Wi-Fi. Devices take turns on the air and retry after interference, so the delay varies from packet to packet. Microsoft points out that the 2.4 GHz band is crowded with household devices and that 5 GHz suits real-time media better.
A busy connection. When an upload or download fills the line, queues in the router grow and shrink, and every packet waits a different amount of time. This is bufferbloat, and it shows up as jitter during transfers.
Congestion at your provider, often in the evening.
VPNs, which add a longer and more variable path.
Weak mobile signal on 4G or 5G.

How to reduce jitter

Use an Ethernet cable for calls and gaming. If you must use Wi-Fi, connect to the 5 GHz band and sit closer to the router.
Pause large uploads, cloud backups and game updates during calls.
Turn on Smart Queue Management (SQM) or QoS in your router if it has it. Microsoft also recommends QoS or WMM on Wi-Fi so voice and video traffic gets priority.
Turn off the VPN for calls, or use split tunneling so call traffic goes direct.
Restart the router and update its firmware.
If jitter is high on a cable at quiet times, contact your provider with your ping test results.

Jitter vs latency vs packet loss

Latency, or ping, is how long one round trip takes. Jitter is how much that time varies. Packet loss is the share of packets that never arrive. They often come together, because the same full queue or weak Wi-Fi causes all three, but a connection can have low latency and still suffer from jitter.

Frequently asked questions

Is 5 ms jitter good?

Yes. It is well under Microsoft's 15 ms and 30 ms targets, and you will not notice it on calls or in games.

Is jitter the same as ping?

No. Ping is the delay of a round trip. Jitter is how much that delay changes between packets.

Does jitter affect download speed?

Not directly. Downloads measure how much data arrives per second, and buffering hides timing changes. Jitter matters for real-time traffic such as calls, live streams and games.

Can a VPN reduce jitter?

Rarely. A VPN adds distance and another server to the path. It can only help when your provider's normal route is badly congested and the VPN's route avoids it.

Sources and further reading

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