This internet jitter test measures how steady your connection’s delay is. Jitter is the headline number above, with ping, download, upload and packet loss alongside it. Run it on the device and connection you use for games or calls.
What is jitter?
Jitter is variation in delay. Every time data crosses the internet it takes a little time (latency, or ping). Jitter describes how much that time changes from one moment to the next. In networking it is also called packet delay variation.
Two example connections (illustrative numbers, not from your test):
- Steady: 20 ms, 21 ms, 19 ms, 22 ms. The delay barely moves, so jitter is low, about 2 ms.
- Unsteady: 20 ms, 70 ms, 25 ms, 95 ms. The delay jumps around, so jitter is high, about 55 ms.
Both start at 20 ms, but the second will feel far worse in a call or game because packets arrive out of rhythm.
Jitter vs. ping and latency
Ping (latency) is how long a round trip takes. Jitter is how much that time varies. They are measured from the same samples but answer different questions, so a connection can have any combination:
- Low ping, low jitter: responsive and consistent.
- Low ping, high jitter: usually quick, but with sudden delays.
- High ping, low jitter: a steady but noticeable delay that apps can adapt to.
- High ping, high jitter: slow and unpredictable.
Real-time apps cope with a steady delay far better than an unpredictable one, which is why jitter matters. It is still only one part of the picture alongside ping and packet loss. You can test your ping on its own page.
How this jitter test works
Before the speed tests start, your browser sends 21 small requests to the test server while the connection is idle, and times each round trip. Jitter is the average difference between each round-trip time and the one before it. If ping goes 20, 22, 21, 35, 20 ms, the differences are 2, 1, 14 and 15 ms, so jitter is 8 ms.
Those round-trip times are measured; jitter is calculated from them. The engine also measures ping during the download and upload tests (shown as ping while downloading and uploading under “Test details”), but the jitter figure shown is from the idle samples.
This is close in spirit to the jitter figure voice and video apps calculate (defined in the RTP standard, RFC 3550), but it is not identical. Apps measure jitter on their own audio and video packets during a call, which can show different values from a short test. Full details are on our methodology page.
What is a good jitter?
Lower and steadier is better for real-time use. This is general guidance, not a universal standard:
| Jitter | What to expect |
|---|---|
| Under 10 ms | Very steady. Calls and games should be smooth. |
| 10–30 ms | Usually fine. Apps buffer a little to smooth it out. |
| Over 30 ms | Choppy audio, frozen video frames and inconsistent game feel become more likely. |
As a reference point, Microsoft’s guidance for Teams targets packet jitter under 30 ms from your device to its network. The activity summary in this tester uses its own guideline of jitter at or under 15 ms (with ping at or under 50 ms) for a “should work well” gaming verdict; that is our guideline, not an industry requirement.
Jitter for gaming
Online games send a steady stream of small position and action updates. When the delay keeps changing, some updates arrive late and others bunch up. That shows up as sudden lag, delayed actions, other players jumping around (rubber-banding), intermittent stutter and a game that feels less responsive than its ping suggests. A steady 50 ms often plays better than a ping swinging between 20 and 120 ms.
No jitter figure guarantees good gaming, and game makers don’t publish a common limit. See our gaming guide for how jitter fits with ping and packet loss.
Jitter for video calls, voice chat and cloud gaming
Calls and voice chat send small audio and video packets at regular intervals. The receiving app expects them in rhythm. When some arrive late, the app must either wait (adding delay) or carry on without them (causing gaps), which you hear as choppy or robotic audio and see as frozen video. Streaming video avoids this by loading several seconds ahead, which is why Netflix can play smoothly on a connection that makes calls unusable.
Cloud gaming is sensitive in both ways: it streams video to you in real time and needs your inputs back quickly. For more on calls, see internet speed for video calls.
What causes high jitter?
Jitter usually comes from packets having to wait a varying amount of time somewhere along the path. Common causes:
- WiFi interference from neighbors’ networks, microwaves, Bluetooth and distance from the router.
- Busy or weak WiFi, where devices compete for airtime and lost wireless frames are resent.
- Competing traffic on your own connection, like a download, upload or backup.
- Queueing and bufferbloat in your router or modem when the connection is full.
- An overloaded router or other local network problems.
- Congestion on your provider’s network at busy times.
- The network path: routing changes, long distances or a VPN adding an extra hop.
- Mobile networks, where signal and cell load change constantly.
What causes jitter spikes?
It helps to tell two patterns apart:
- Consistently high jitter often points to a weak or crowded WiFi link, a busy network path or a mobile connection.
- Normally low jitter with occasional spikes often points to something that comes and goes: another device starting a download or backup, a burst of WiFi interference, an update, or congestion at certain times.
Occasional spikes can be especially noticeable in games and calls, because a single large delay causes a freeze or a lag spike. Run the test a few times, note when spikes happen, and check what else was using the connection then.
Jitter vs. latency, packet loss and speed
| Metric | What it measures | Why it matters |
|---|---|---|
| Ping / latency | Round-trip delay | How quickly actions and replies arrive |
| Jitter | How much that delay varies | Smoothness of calls and games |
| Packet loss | Share of test packets that never arrive | Gaps, glitches and disconnects |
| Download speed | How fast data reaches you | Streaming, downloads, page loads |
| Upload speed | How fast data leaves your device | Your video on calls, backups, sending files |
A fast download doesn’t mean low jitter, and a low ping doesn’t guarantee it either. Jitter and packet loss often appear together, because the same congestion or WiFi trouble that delays some packets can drop others.
WiFi vs. Ethernet and jitter
WiFi is a shared radio link. Distance, walls, interference from nearby networks and devices, and other devices taking turns to transmit can all make delay less consistent. A cable removes those wireless variables, so comparing a wired test with a WiFi test is one of the most useful checks you can make. Ethernet doesn’t eliminate jitter caused further along the path, though.
On WiFi, the band matters too: 2.4 GHz reaches farther but is often more crowded, while 5 GHz and 6 GHz are often less congested at shorter range. The best choice depends on your router, device and where you sit. Keep in mind that WiFi speed, signal strength, latency and jitter are different measurements; a strong signal can still have high jitter if the channel is busy. Test your WiFi connection or follow our guide to testing WiFi around your home.
VPNs, ISP routing and server distance
Jitter depends on the whole path between your device and the server: your provider’s network, the transit networks and peering points it hands traffic to, and the distance to the destination. Congestion at any point, or a route that changes, can make delay less consistent. A VPN adds its own server to the path, and a busy or distant VPN server can increase jitter.
That is why a test to one server may not match a game or call using another server: the route and the congestion along it can be different.
Loaded latency, congestion and bufferbloat
When a large download or upload fills your connection, data queues up in your router, modem or the network. Every new packet, including game and call traffic, waits behind the queue, and the wait changes as the queue grows and shrinks. That raises delay and makes it less consistent.
Excessive queueing like this is called bufferbloat. It isn’t the same thing as jitter, but it is a common cause of high and unstable latency when someone else is using the connection. Compare ping while downloading and uploading under “Test details” with your idle ping, use the bufferbloat test, or read what bufferbloat is.
How to reduce jitter
Retest after each step. Not every step will help every connection.
- Stop background downloads and uploads. Useful when jitter rises while other devices are busy.
- Test close to the router. Shows whether distance and walls are the problem.
- Compare WiFi with Ethernet. If jitter drops on a cable, the cause is inside your home network.
- Restart the router, and update its firmware if it has been running a long time or is out of date.
- Check for heavy traffic from other devices, such as streaming, game updates and cloud backups.
- Try another WiFi band if your router and device support 5 GHz or 6 GHz.
- Test with and without a VPN to see whether it adds instability.
- Check whether it only happens at busy times, which points toward congestion.
- Check for bufferbloat. Smart queue management (SQM) on a router is often the most effective fix.
- Contact your provider if high jitter persists across devices and on a wired connection.
This test connects to the nearest Cloudflare location automatically and doesn’t let you choose a server, so comparing locations isn’t possible here. Our guide on reducing jitter goes through the fixes in more detail, and reducing ping covers related steps.
Troubleshooting jitter by pattern
These patterns may indicate likely areas to check; they are not certain diagnoses:
- Low ping with occasional large jitter spikes: often points to WiFi interference, congestion, background traffic or an unstable route.
- High ping and high jitter: may point to distance, congestion, routing or an overloaded network path.
- Low jitter on Ethernet, high on WiFi: wireless or local network conditions.
- Jitter high only during heavy downloads or uploads: queueing or bufferbloat.
- This test looks good but a game is still unstable: a different game server or path, routing, peering, or conditions on the game’s side.
What your jitter result means
- Low jitter: your connection to the test server was steady during the test.
- Moderate jitter: usually fine, but calls and fast games may show occasional hiccups. Check again at busy times.
- High jitter: delay was unsteady. Repeat the test, compare WiFi with a cable, and look for other traffic.
Read jitter together with ping and packet loss. The tester’s activity summary does this for you, using the guidelines described above.
Limitations of a browser-based jitter test
- It measures the path to its own measurement infrastructure, not to every server you use.
- Results can vary with server location, time of day and changing ISP routes.
- WiFi conditions can change from minute to minute.
- In-game and in-call jitter may differ, because those apps use their own servers and protocols.
- Browser measurements are not identical to ICMP ping or other network diagnostic tools.
- It does not measure every hop along the path or diagnose your provider automatically.
- One test is a snapshot; a few tests at different times tell you more.
About this test
This website uses Cloudflare’s open-source speed test engine. It is independent and is not affiliated with or endorsed by Cloudflare. Every number comes from your own test. Read our methodology, learn who runs this site, or see what data the test sends.