Understand every metric — download, upload, ping, jitter, packet loss — and how DCSpeedTest compares to Ookla and…
Cable internet connections are asymmetric — typical cable internet provides 10-50 Mbps upload vs 200-1,000 Mbps download. Fiber is symmetric — AT&T Fiber…
Why does a speed test use multiple parallel connections instead of one?
A single TCP stream can't fill high-speed connections above 100 Mbps due to TCP's built-in congestion control, so speed tests open 4-16 parallel streams…
A speed test is a measurement tool that quantifies the performance of your internet connection at a specific moment in time. It does this by temporarily…
Ping is determined primarily by your connection technology: Fiber (4-12ms) < Cable (10-25ms) < 5G mobile (25-45ms) < 4G LTE (45-75ms) < Satellite (20-60ms…
Why does DCSpeedTest report the median result instead of the peak speed?
The median is more resistant to brief spikes and dips caused by momentary network events during the roughly 10-second test window, giving a result that…
Understanding how a speed test works helps you interpret results and avoid common testing mistakes:
Jitter measures the variation in ping over time. A ping of 20ms with 2ms jitter is much better than a ping of 20ms with 15ms jitter, because:
Why might Ookla show a higher speed than DCSpeedTest on the same connection?
Ookla tests route to servers hosted by the ISPs themselves, and some ISPs have been documented prioritizing traffic to their own test servers, while…
The speed test sends a tiny ICMP or TCP packet to the test server and measures the round-trip time in milliseconds. This is your ping. It also sends multiple ping…
Under 5ms jitter = excellent. 5-15ms = good. 15-30ms = marginal. Above 30ms = investigate. High jitter usually indicates network congestion, WiFi…
Understand every metric — download, upload, ping, jitter, packet loss — and how DCSpeedTest compares to Ookla and Fast.com.
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