AltF NetCheck
Jitter Test
This jitter test measures how much your latency changes from one moment to the next. It takes 20 ping samples to the nearest Cloudflare server and reports jitter as the average difference between consecutive samples, shown on a live bar chart so spikes are visible. Under 15 ms is good for gaming and under 30 ms for video calls.
- Free, no sign-up
- Cloudflare global network
- Ping, jitter and bufferbloat
- History stays on your device
Run the internet speed test
-Mbps
-Mbps
-ms
Idle round-trip time
-ms
Ping variation
-ms
Measured during download and upload
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Grade A+ to F
Your connection
Run a test to see your ISP, public IP (masked by default), approximate location and the server you were tested against.
The test talks to Cloudflare's speed-test servers, which see your IP address like any website does. AltFTool does not store your results; history stays in this browser.
Your speed history
Every test you run is saved here, in this browser only, so you can compare times of day, rooms or Wi-Fi vs cable. Nothing is uploaded.
What jitter does to calls and games
Real-time apps play audio and video at a steady rate, so packets that arrive late or bunched up have to be buffered or dropped. Small, steady jitter is absorbed invisibly; large jitter shows up as robotic voices, frozen video frames and players teleporting in games, even when your ping and speed look fine.
Jitter ranges
- Under 5 ms: excellent and typical of a wired fibre connection.
- 5-15 ms: good for gaming and calls.
- 15-30 ms: acceptable for calls, noticeable in fast games.
- Over 30 ms: unstable; expect choppy calls.
How to reduce jitter
- Switch to Ethernet or move closer to the router; Wi-Fi is the most common cause.
- Stop large downloads and uploads on the same line during calls.
- Enable SQM or QoS on the router to stop queues from building up.
- Replace old routers and powerline adapters that add delay spikes.
- On mobile data, test from a spot with a stronger, more stable signal.
Jitter Test FAQ
What is jitter in internet speed?
Jitter is the variation in ping over time, in milliseconds. A connection with 30 ms ping and 2 ms jitter feels smooth; one with 30 ms ping and 40 ms jitter feels unreliable.
What is a good jitter for gaming?
Under 15 ms is good, and under 5 ms is excellent. Above 30 ms most online games show lag spikes.
Can my ISP fix jitter?
If jitter is high on a wired connection with nothing else using the line, it may be congestion or a fault on the ISP's side, and your saved results are useful evidence. Jitter that only appears on Wi-Fi or when the line is busy is fixed at home.
Want the complete picture? The main page explains every result, how much speed each activity needs, why tests read lower than your plan and how NetCheck measures.
Internet speed test guideAltFTool stores no results and no IP addresses. Tests run against Cloudflare's speed-test servers; your history is kept in this browser only.