The headline number
For a simple visual reaction — one signal, one response, a healthy adult, a screen and a click — the average lands in the 200 to 300 millisecond band, and large public aggregates put the median close to 273 ms. A quarter of a second is a fair thing to carry in your head.
That figure is for simple reaction time. Change one condition and it moves substantially. Respond to a sound instead of a light and you gain 30 to 50 ms. Add a decision about which signal you are seeing and you lose 50 to 150 ms. Measure a spinal reflex instead of a reaction and you are down in the 30 to 50 ms range, which is a different measurement entirely.
Averages by condition
| Measurement | Typical adult range |
|---|---|
| Simple visual reaction, screen and click | 200 to 300 ms |
| Simple auditory reaction, tone and click | 160 to 250 ms |
| Choice reaction, two or more options | 300 to 450 ms |
| Sprint start reaction to the gun (elite) | 120 to 180 ms |
| Driver perception and reaction, real traffic | 0.7 to 1.5 s |
| Spinal reflex, no brain involvement | 30 to 50 ms |
Why your score is probably slower than the average you read about
Laboratory figures are measured with hardware buttons and purpose-built timing equipment. Your browser result includes your monitor, your mouse or touchscreen, your operating system and your browser. That stack routinely adds 20 to 40 ms that a lab result does not contain.
So a 280 ms score in a browser is not slower than a 240 ms score in a published study — they are measuring different things. Comparing your browser result against other browser results, and against your own results on the same device, is the only comparison that means anything.
The corrected figure shown with your result removes the part of that stack we can calculate: the average wait for your screen's next refresh.
What genuinely moves the average
- Age. Simple reaction time is fastest in the late teens and early twenties and slows gradually through adult life.
- Sleep. A short night is one of the largest single-day effects there is, and it hits consistency even harder than speed.
- Alertness and time of day. Most people are slowest in the early morning and in the post-lunch dip.
- Practice with the specific task. Simple reaction time barely improves; decision speed on a familiar task improves a lot.
- The device. Phone, laptop trackpad, wired mouse and gaming monitor produce meaningfully different numbers for the same person.
Reading your own result
Take the average of five trials rather than your best single one — the best trial is partly luck, and a run of five tells you about your consistency as well as your speed. Then look at the spread. A tight cluster means you were focused. A single slow trial dragging the average usually means a lapse of attention rather than a slow nervous system.
If you want to know whether something changed you — a night of poor sleep, a coffee, a new monitor — run the test before and after on the same device, five trials each, and compare averages. A difference under about 15 ms is noise.