Free Online Reaction Time Test

The average simple visual reaction time for a healthy adult is approximately 250 milliseconds (ms). Auditory reaction times are faster, commonly averaging around 150–170 ms, because the auditory pathway reaches motor areas through fewer stages than the visual pathway, which detours through the visual cortex first. These figures represent the gap between a stimulus appearing and a response arriving — they do not include decision-making or complex motor sequences. Age, fatigue, and practice all shift the individual baseline, but 200–300 ms covers most healthy adults under simple test conditions. See our methodology page for what this site can and cannot measure.

A genuine 100 ms simple reaction time is physiologically possible but extremely rare. The lower bound set by nerve conduction velocity and synaptic transmission is roughly 100–120 ms for a simple reflex arc from eye to hand. Achieving 100 ms consistently in a browser-based test almost certainly involves anticipation — pressing just before the signal — rather than true reaction. On this site a result below about 130 ms is worth scrutinising: the too-early detector catches presses before the signal, but a very well-timed pre-press that lands just after onset can still register as a legitimate result. Elite athletes and fighter pilots occasionally record 120–140 ms under laboratory conditions, but 100 ms is at or below the practical floor.

You can test your reaction time right here. Select a mode from the switcher at the top of the test page — Ruler Drop, Color Change, Fake-Out, Speed Click, or 5-Trial Challenge — activate the surface, wait for the signal, and respond as quickly as possible. The browser high-resolution timer records the milliseconds between signal onset and your input. For the most accurate reading: use a wired or built-in keyboard or mouse rather than Bluetooth; enable latency compensation in the Calibration section to subtract your input pipeline delay; and run at least five attempts so the mean rather than a single lucky result represents your baseline. Each mode keeps its own history, so you can compare your scores separately.

Yes, reacting within 0.2 seconds (200 ms) is well within the normal range for a simple visual stimulus. Published averages put the population mean around 250 ms, which means a substantial portion of healthy adults react in under 200 ms under good conditions. Factors that help include high alertness, familiarity with the task, a high-refresh-rate display that reduces the frame delay before the signal appears, and low ambient stress. Audio reaction to a tone typically comes in around 150 ms, comfortably below 200 ms for most people. So 200 ms is fast but not exceptional — it sits in roughly the top third of the population for visual stimuli.

A confirmed 120 ms reaction time to a simple visual stimulus would be exceptional — placing the person at or very near the physiological limit set by nerve conduction speed. Under rigorous laboratory conditions with EEG-controlled signal delivery, the fastest reliably recorded simple visual reactions sit around 120–130 ms. On a standard browser test, a 120 ms reading is almost always the result of anticipation, a lucky pre-press, or an unusually low-latency hardware setup combined with genuine speed. If you are consistently recording 120–140 ms with the latency compensator on and without early-response flags, your reflexes are in elite territory. Most people measuring below 150 ms should verify the reading with the ready-gate calibration enabled, which prevents anticipatory presses.

Formula 1 drivers are often cited as having reaction times of around 150–200 ms at race starts — measured from the lights going out to the car moving. This is a practised, anticipated response rather than a pure simple reaction time: drivers know the exact signal, its timing window, and the precise motor sequence required. Pure laboratory reaction times for F1 drivers are not dramatically faster than the general population; what distinguishes them is consistency under stress, the ability to process multiple inputs simultaneously, and trained anticipation. One correction to a widely repeated claim: Formula 1 does not disqualify a driver for reacting in under 100 ms. The sport previously applied a fixed reaction-time threshold, but it was abandoned once timing data showed drivers legitimately reacting faster than it. Today a jump start is judged on whether the car physically moved before the start signal, detected by the FIA transponder at each grid slot and reviewed by the stewards on video.

This site does not answer that question, and we are not the right source for it. Reaction time is not a diagnostic measure and this test cannot assess ADHD or any other condition. What the published literature broadly reports is that ADHD groups show greater variability in response times — a wider spread between fastest and slowest trials — rather than a reliably faster or slower average, and that performance on long vigilance tasks tends to decline more steeply than in comparison groups. Medication status, task design, and individual differences all affect these findings. If you are wondering about your own attention or response patterns, that is a conversation for a qualified clinician, not a web test. See our sources page for what this site cites and what it deliberately does not claim.

There is no fixed lower bound to human reaction time — it depends on the state of the individual and the complexity of the task. Under simple test conditions, healthy adults rarely exceed 600–700 ms consistently; readings in that range usually indicate distraction, fatigue, or very high anxiety. Older adults commonly average 300–400 ms on simple visual tasks. Choice reaction time — where the response depends on which of several stimuli appeared — adds time as the number of options grows, an effect usually described by Hick's Law. Impaired or sedated individuals can register seconds, not milliseconds. For practical purposes, a reading far above your own recent average almost always means something changed about the test conditions rather than about you: check for a Bluetooth input device, a busy browser, or a low battery before treating a single outlier as a real result. This test is not a medical assessment and cannot diagnose anything.

A human cannot reliably react to an unpredicted stimulus in 100 milliseconds. The minimum time needed to perceive a visual signal, transmit the nerve impulse, and execute a motor response is approximately 100–120 ms under ideal conditions, leaving no margin for variability. Results at exactly 100 ms on a standard test almost always reflect anticipation. Auditory reactions can come closer — the fastest confirmed laboratory audio reactions sit around 100–110 ms — but these are outliers, not the norm. The 100 ms figure is better understood as the theoretical physiological floor than as a routinely achievable result. Most studies put the practical minimum for a genuine unpredicted reaction above 120 ms.

No single verified world record exists for the fastest human reaction time under controlled conditions, partly because methodology varies widely between studies. High-speed athletes — professional cricket batsmen, table tennis players, and baseball hitters — regularly react to incoming objects in under 200 ms, but those involve practised pattern recognition rather than simple reaction. In pure laboratory simple-reaction-time studies, the fastest confirmed readings in peer-reviewed research sit around 120–130 ms for visual stimuli and around 100–110 ms for auditory. Guinness World Records has historically not maintained a reaction-time category because the measurement is too dependent on equipment and protocol. Athletes in sports requiring rapid response — sprinters, combat sports competitors, racket sport players — consistently score in the 150–200 ms range in laboratory settings.

Yes, age is one of the most consistent predictors of reaction time. Simple visual reaction time peaks in the early to mid twenties, plateaus through the thirties, and then slows by roughly 1–2 ms per year from the forties onward. Using the same cross-sectional reference figures as our main FAQ, published averages run approximately 210 ms at 18–24, 225 ms at 25–34, 240 ms at 35–44, 255 ms at 45–59, and around 285 ms at 60 and over. The slowing reflects changes in neural conduction speed, synaptic efficiency, and sensory processing rather than motivation or practice. Regular aerobic exercise is associated with smaller age-related slowing in several studies, and continued task-specific practice helps maintain speed into later life. Individual variation inside any single age band is wider than the gap between bands, so treat these as reference points rather than targets.

Several common factors can slow a reaction time result beyond your natural baseline. Fatigue is the most frequent culprit: even mild sleep restriction reliably adds 20–50 ms to mean reaction time. High stress or anxiety narrows attention in ways that can delay response. Alcohol slows conduction speed noticeably even below the legal driving limit. Cold hands or fingers increase motor execution time. Device latency — the gap between your input arriving at the hardware and the browser receiving it — can add 20–80 ms depending on the connection type; the latency compensator in the Calibration section measures and subtracts this. Finally, unfamiliarity with the task means the first few attempts are always slower; run at least ten trials before treating the mean as representative.

To test your reaction time, open the test page, pick a mode — Ruler Drop, Color Change, Fake-Out, Speed Click, or 5-Trial Challenge — and activate the test surface with a click, tap, or the Space key. Wait without pressing anything; the test starts a random delay of one to three seconds before the signal appears. Respond the instant you see the signal. Your result in milliseconds appears immediately, along with an estimated percentile. Run at least five attempts to get a reliable mean. For a more accurate result, turn on latency compensation in the Calibration panel first: it runs five rounds to measure your input pipeline delay and subtracts it from every subsequent result.

For an accurate reaction time measurement, four things matter most. First, eliminate anticipation: use the ready-gate calibration control, which holds the signal until you explicitly confirm you are ready, preventing pre-presses. Second, subtract input latency: the latency compensator in Calibration measures your device's input pipeline over five rounds and deducts the median from your result. Third, use wired or built-in peripherals: Bluetooth keyboards and mice add 20–100 ms of variable delay that the compensator cannot fully account for. Fourth, test in a consistent state — same time of day, same alertness level — and use the mean of at least ten attempts rather than a single result. The 5-Trial Challenge mode averages five consecutive trials automatically, which is harder to game than a single lucky catch.

There is no universally accepted single world record for reaction time because results depend heavily on methodology: the type of stimulus (visual vs auditory), the input device, the measurement software, and whether the test guards against anticipation. In peer-reviewed research, the fastest confirmed simple visual reaction times are around 120–130 ms and the fastest auditory reactions around 100–110 ms. Guinness World Records does not maintain an active reaction-time category. Various online leaderboards report sub-100 ms results, but these almost always reflect anticipation, display latency not accounted for, or hardware timing shortcuts rather than genuine neural response speed. A result below about 130 ms on any browser-based test should be treated with scepticism unless anticipation controls were active.

Testing reaction time at home is straightforward with this site. Open the test page on any device — phone, tablet, or desktop — pick a mode, and start testing. No equipment is needed beyond the device itself. For the most honest home measurement: sit comfortably with your hand resting near the keyboard or screen; run at least ten attempts; ignore the first two or three while you settle into the task; and take the mean of the remaining results as your baseline. Enable latency compensation in the Calibration panel so the device's input pipeline delay is subtracted. If you use a touchscreen, tap speed can vary with finger angle — use a consistent, light tap near the centre of the surface for repeatability. The 5-Trial Challenge mode produces a single averaged score from five trials, which makes it the best single-session home measurement.