Our Measurement Method
A test is only as trustworthy as its method. Here is exactly what we measure on api.speedtest.doctor, how we keep the numbers honest, and where the limits are.
Every figure on speedtest.doctor comes from measurements against our self-hosted endpoints at api.speedtest.doctor — download, upload and latency probes on infrastructure we control. We report stability rather than a lucky peak, and we're upfront about what a browser test can and can't tell you.
What each metric means
Download / Upload
Parallel streams to multiple high-bandwidth endpoints; we report a stable aggregate, not a single lucky burst. Throughput ramps up before we start counting, so slow-start doesn't drag the number down.
Ping (latency)
Round-trip time sampled repeatedly against several servers. We surface the median and the spread, not just the best result — a single low ping can hide a shaky line.
Jitter
Variation between consecutive latency samples. Low jitter means a steady line; high jitter is what makes calls choppy even when the average looks fine.
Packet loss
The share of probes that never come back, measured over a sustained window rather than a quick burst, so transient blips don't masquerade as a healthy line.
Bufferbloat
Added latency while the link is saturated. We compare idle ping to ping-under-load — the gap is the metric that ruins gaming and video calls.
DNS
Resolution time across common public resolvers, so you can see whether name lookups (not bandwidth) are what makes pages feel slow to start.
Principles
- Multiple servers per test to reduce single-point bias.
- We report ranges and stability, not just peak figures.
- Idle vs under-load latency are measured separately (that's how bufferbloat surfaces).
- No account required for a basic test; results aren't sold.
- The method evolves with the measurement engine — this page is the source of truth.
Honest about the limits
No browser-based test is perfect. We'd rather tell you why than pretend otherwise.
Your device matters
An old phone, a busy CPU or a weak Wi-Fi radio can cap results below what your line can do. Test wired when you want the line's true ceiling.
Wi-Fi is a variable
Distance, walls and interference change results room to room. We measure your connection as it reaches this device — not the theoretical plan speed.
Time of day counts
Evening congestion is real. One test is a snapshot; re-running at peak hours reveals patterns a single run can miss.