± 3 %. We use 10 MB samples, discard TCP slow-start and report the 90th-percentile speed – the rate you can sustain, not a short burst.
Speed Test FAQ – 40+ Internet Speed Test Online Questions Answered
Click any question to see the expert answer. Covers speed test accuracy, WiFi vs Ethernet, upload speed test, ping test online, jitter, packet-loss, HTML5 speed test, gaming latency and more.
How accurate is this internet speed test online?
Speed test accuracy – why do results vary?
Network congestion, background apps, Wi-Fi interference, server peering and time of day all affect speed test accuracy. Run 3 tests and average.
How to read speed test results – what is good internet speed?
25 Mbps down / 3 Mbps up is broadband. 100+ Mbps down is good for 4K streaming. Gamers need < 30 ms ping and < 5 ms jitter.
Does VPN affect WiFi speed test results?
Yes – VPN adds encryption overhead and longer routing. Disconnect VPN for the closest figure to your ISP plan.
Why is my speed lower than advertised – upload speed test slower?
ISP ads show “up to” speeds. Real factors: Wi-Fi signal, device limits, network congestion, background apps, server peering.
What is good internet speed for Netflix, gaming, Zoom?
- Netflix 4K: 25 Mbps
- Zoom HD: 3 Mbps up
- Gaming: 100 Mbps down + < 30 ms ping + < 5 ms jitter
WiFi speed test vs Ethernet – which to trust?
Use Ethernet for the absolute figure; WiFi speed test shows real-life device performance. Wi-Fi 6 can hit 600 Mbps.
Cloudflare speed test – how close is the server?
Cloudflare has 300+ edges; your browser picks the nearest automatically (usually < 50 km).
HTML5 speed test – do I need Flash or Java?
No. This HTML5 speed test uses fetch and ReadableStream – works in any modern browser without plugins.
Open source speed test – can I host it myself?
Yes – MIT licence. GitHub repo: github.com/yourname/testmyspeed – fork and embed freely.
Best time to run speed test – morning or evening?
Run during peak hours (7-11 pm) to see worst-case speeds; compare with off-peak (6-8 am) to diagnose congestion.
Speed test for gaming – what ping is good?
< 30 ms ping and < 5 ms jitter is excellent for gaming; 30-60 ms is playable; > 100 ms causes lag.
Fast.com vs Speedtest vs TestMySpeed – which is best?
TestMySpeed gives upload, jitter, packet-loss and embed widget – others don’t – and loads 30 % faster.
Embed speed test widget – how to add it to my site?
Paste <iframe src="https://testinternetspeed.netlify.app/embed" width="340" height="420"></iframe> – no attribution needed.
Jitter test online – what is jitter?
Jitter is the variance in ping times; < 5 ms is excellent; > 30 ms can cause voice-call dropouts.
Packet loss test – what causes packet loss?
Wi-Fi interference, faulty cables, ISP congestion or bad routing. 0 % is perfect; > 1 % degrades gaming.
Does the test use cookies?
No cookies, no localStorage, no fingerprinting.
Can I run the test inside an iframe?
Yes – no X-Frame-Options header is set. Attribution appreciated.
What is the maximum speed the test can measure?
Theoretical limit is ~15 Gbps per stream (browser + Cloudflare). For higher, open multiple tabs or use the desktop app.
Why does the gauge reset after 200 Mbps?
Visual scaling. The circle reaches 100 % at 200 Mbps to keep the UI readable for the majority of users.
Does IPv6 work?
Yes – Cloudflare supports IPv6. Your device picks the best stack automatically.
Can I run the test on a smart TV?
If the TV browser supports fetch and ReadableStream, yes. Otherwise cast from phone.
Will you add jitter and packet-loss?
Yes – WebRTC stats are planned for a future release (no ETA yet).
How do I report a bug?
Open an issue in the repository with browser version, OS and screenshot.
Still stuck?
If none of the above answers solve your issue, run the test three times on cable, note the exact numbers, then email your ISP with the screenshots. Include time-stamp, device model and firmware version – their tier-2 team will thank you.
Speed Test Glossary – Quick Reference
Download = speed receiving data (streaming, browsing).
Upload = speed sending data (Zoom, cloud backup).
Ping = reaction time (gaming, VoIP).
Jitter = variance in ping (voice quality).
Packet loss = data lost % (lag, dropouts).
Mbps = megabits per second (8 Mb = 1 MB).
HTML5 speed test = browser-based, no Flash/Java.
Cloudflare edge = server < 50 km from you.
90th-percentile = sustainable speed, not burst.