Reaction Time Test — your reflexes vs your ping

How to play

1. 1Tap the panel (or press Space) to start. It turns dark and waits a random one to three-and-a-half seconds.
2. 2The moment it turns green, tap or press Space. Your time in milliseconds appears on the panel and drops onto the ladder below.
3. 3Tap before green, or within 100 ms of it, and the round is a false start — it is replayed, not counted.
4. 4Five counted rounds make a run. Your score is the average; your best single round is kept as a personal best.
5. 5Run the speed test first and your own ping appears on the ladder next to fibre, 5G, LTE and satellite.

What your number means

The score is the average of five counted rounds, which is the figure the well-known reaction-time tests report, so you can compare directly. Under 180 ms is Lightning, under 220 ms Elite, under 260 ms Sharp, under 320 ms Average, under 400 ms Relaxed, and anything slower is Unhurried. Your best single round is tracked separately as a personal best and is shared with the reflex game on the speed-test page.

Expect your number to move by 20–40 ms between devices and between a fresh morning and a late night. The trend line under your result compares your recent runs with the ones before, which is a fairer read than any single score. The typing speed test works the same way for your fingers.

Reflexes vs latency: why both numbers matter

A ping figure on its own is abstract. Next to your own reaction time it becomes concrete: on fibre, a round trip to a local server is typically 5–20 ms, so the connection answers ten to fifty times faster than you can tap. When a call or a game feels laggy on a line like that, the delay is in the Wi-Fi, the router's queue, or the far end — not the fibre. Our guide to reading a speed test explains what ping and jitter measure, and your connection history keeps every result you have recorded on this device.

The ladder places your average on a logarithmic scale from 1 ms to 1,000 ms alongside typical round trips: fibre, 5G, fixed LTE, a blink, Johannesburg to Cape Town, London, New York and Sydney, and a geostationary satellite. The route and link figures are typical ranges, labelled as such; your ping is the only measured value, read from your most recent speed test on this device. For how those link types differ in practice, see fibre vs LTE vs 5G, and for why LTE ping climbs when the lights go out, see internet through load-shedding.

How this test measures

The cue is timed from the display frame that actually painted the green panel, using a double requestAnimationFrame, so React's render cost is not charged to you. Input is read on pointer-down rather than click, which fires later on touch screens. The panel deliberately has no colour transition when it turns green — a fade would delay the cue and inflate every score.

Reactions under 100 ms are rejected as anticipation: no human responds to a visual cue that quickly, so a tap that lands sooner was started before the cue. A cue left for five seconds is a miss and the round is replayed. Switching tabs or locking the phone pauses the round rather than recording a nonsense time. The ping on the ladder is measured the way the network diagnostic methodology describes.

Frequently asked questions

What is a good reaction time?

On a screen-based test like this one, an average of 200–250 ms is quick, and large online tests report medians of roughly 270 ms. Laboratory studies with dedicated hardware record 200–250 ms for adults because they avoid the screen refresh and input delays a browser adds. Under about 150 ms is rare, and under 100 ms is not a reaction at all, which is why the test rejects it.

Why does the test reject taps under 100 ms?

Simple reaction to a visual cue does not go below about 100 ms in humans — the eye, the nerves and the muscle all take time. A tap that lands sooner than that was started before the cue appeared, so it counts as a false start and the round is replayed. World Athletics applies the same rule: a sprinter who leaves the blocks less than 0.100 s after the gun is charged with a false start.

Why is my ping so much lower than my reaction time?

Because a packet on fibre travels at roughly 200,000 km per second and your nervous system does not. A round trip to a server in the same country is typically 5–20 ms on fibre, so a 250 ms reaction is ten to fifty times slower than the line. The comparison is the point: if a video call feels laggy on a 10 ms connection, the delay is somewhere other than the internet. The only common link a human can beat is geostationary satellite, at around 600 ms.

Will I get the same score on a phone and a PC?

Not exactly. A 60 Hz screen only redraws every 16.7 ms, a touchscreen samples your finger at a fixed rate, and a wireless mouse adds a few milliseconds of its own, so the same person scores differently on different hardware. The test timestamps the frame that actually painted the green cue and reads your input on pointer-down to keep the overhead as small as possible, but compare yourself against your own history on the same device rather than against a friend's laptop.

Where are my results stored?

Only in your browser's localStorage on this device: your last 20 runs, your best average, your day streak and your best single round. Nothing is sent to a server and there is no account. The best single round is the same figure the reflex game on the speed-test page uses, so beating it in either place updates both. Clearing your browser data clears the lot.

Where do the fibre, 5G, LTE and satellite figures come from?

They are typical round-trip ranges for those link types in South Africa, labelled as typical rather than measured: fibre to a local server 5–20 ms, 5G 20–40 ms, fixed LTE 30–60 ms, geostationary satellite around 600 ms. The route figures (Cape Town, London, New York, Sydney) are typical pings from Johannesburg. Your own ping dot is the only measured value on the ladder, taken from your most recent speed test.