What Is Jitter? Good Jitter for Calls and Gaming, and How to Fix It
Ping tells you how long a round trip takes. Jitter tells you how much that time keeps changing. If one request takes 20 ms, the next 70 ms and the next 25 ms, your average ping looks fine but the connection does not feel fine. That unevenness is jitter, and it is behind a lot of problems people blame on slow internet.
A speed test sends a series of small requests and times each one. Jitter is the average difference between one result and the next. On FastSpeedTest, 12 requests are sent 50 ms apart, and jitter is the mean of the gaps between consecutive round trips. The details are on the methodology page .
Video call apps keep a small buffer so audio plays smoothly. If packets arrive at a steady pace, even with some delay, the buffer handles it. When arrival times jump around, packets arrive after their moment to play, and you hear gaps or robotic voices. Games work the same way: they can predict a steady delay, but not a changing one, so other players seem to teleport.
On this page
- How jitter is measured
- What counts as good jitter
- Why jitter hurts more than high ping
- The usual causes
- How to find the cause yourself
- How to lower jitter
- What is a good jitter?
- Is jitter worse than high ping?
- What causes jitter?
- How do I reduce jitter?
You can put any two of these tests side by side with the compare tool .
Key points
- Wi-Fi. Radio interference, walls and neighbouring networks make each packet's trip a little different. This is the most common cause in homes.
- Other traffic on your line. When someone uploads photos or a console downloads an update, your packets wait in a queue that keeps changing length.
- Bufferbloat. Routers with large queues let delay pile up under load. Ping looks fine at idle and jumps when the line is busy. See bufferbloat explained .
- Evening congestion. A busy provider network adds variable delay at peak hours.
- Run a test on Wi-Fi and note the jitter.
- Run the same test on a cable. If jitter drops a lot, Wi-Fi is the cause.
- Run a test while a large download is running on another device. If jitter jumps, it is bufferbloat or queueing.
- Run a test in the morning and again in the evening. If only evenings are bad, it is probably congestion outside your home.
- Use Ethernet for the device that matters most: the gaming PC, console or work laptop.
- On Wi-Fi, use the 5 GHz band near the router and avoid crowded channels.
- Schedule backups and large downloads for times you are not on calls.
- If your router offers smart queue management, often called SQM or QoS, turn it on. It keeps queues short under load.
- If jitter stays high on a cable at all hours, contact your provider with your test results and times.
- Perfect, even for fast shooters
Frequently asked questions
- What is a good jitter?: Under 5 ms is excellent and unnoticeable. 5 to 15 ms is fine for calls and most games. 15 to 30 ms starts to show in fast games and can cause small audio glitches. Above 30 ms, calls break up and games feel inconsistent.
- Is jitter worse than high ping?: Often, yes. Apps can adjust to a steady delay, but they cannot predict a delay that keeps changing. A steady 60 ms usually feels better than a 30 ms average with big spikes.
- What causes jitter?: Most often Wi-Fi interference, other devices using the connection at the same time, and router queues filling up during uploads or downloads. Congestion on the provider's network in the evening can add more.
- How do I reduce jitter?: Use a cable, pause heavy uploads and downloads on other devices, move to the 5 GHz band near the router, and turn on smart queue management if your router has it.
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