Start by knowing what can move
Simple reaction time is close to a floor set by biology. A signal has to reach your retina, travel to visual cortex, be recognised as the go-signal, and produce a motor command that travels back down to your finger. That round trip does not go below roughly 100 milliseconds in anyone, and typical adults land near 231 ms on laboratory apparatus according to Woods and colleagues (2015).
So the realistic question is not "how do I make my nervous system faster", because you largely cannot. It is "how much of my current score is avoidable loss", and the answer for most people is: quite a lot. State, technique and equipment together account for far more day-to-day variation than any training programme will.
What actually works
Sleep, by a wide margin. Reaction speed is one of the most reliable casualties of sleep loss, and the effect accumulates. In Van Dongen and colleagues (2003), participants restricted to six hours a night for two weeks showed cognitive deficits comparable to going without sleep entirely for up to two nights, and crucially they rated themselves as only slightly impaired. That last part is the trap: chronic sleep restriction degrades your performance and your ability to notice it at the same time. If you want a faster number tomorrow, sleep is the highest-yield intervention available and it is free.
Time of day. Alertness follows a daily rhythm, and for most people it dips in the early afternoon and again in the small hours. Testing at your personal peak rather than your trough can move a score by more than a month of practice would. It also means that comparing a morning result with a late-night one tells you about your circadian rhythm rather than your ability.
Warming up. Your first run of anything is nearly always your worst, because part of it is spent learning what the task wants. Two or three throwaway rounds before the run you actually count removes a chunk of that. This is not cheating; it is the difference between measuring your reaction and measuring your confusion.
Hardware, more than people expect. A 60 Hz display costs you about 8 ms on average versus a 144 Hz one, simply because the image cannot change until the next refresh. A 125 Hz mouse can sit on your click for up to 8 ms where a 1000 Hz mouse holds it for about 1. Wired beats Bluetooth. None of this makes you faster, but it stops the equipment from making you look slower. See our guide on measurement accuracy for the full chain.
Posture and readiness. Rest your finger lightly in contact with the button rather than hovering above it — you remove the travel distance from the measurement. Keep your eyes near where the signal will appear so it lands in central vision. Breathe out and stay loose; tension slows the motor phase rather than speeding it.
What does not work, or barely does
Most "brain training". Practising a reaction test makes you better at that reaction test. Whether that transfers to anything else is a separate question, and the evidence for far transfer is weak. We wrote about this in what the evidence says about brain training. If your goal is a better number on this page, practice will deliver it — mostly by teaching you the task, not by upgrading you.
Reaction-time supplements. The category is largely marketing. Caffeine is the exception with real evidence behind it, and its effect is modest — useful if you are under-slept or in a circadian dip, close to nothing if you are already rested and habituated. Tolerance builds, so the person who drinks coffee all day gets less from a pre-test cup than the person who does not.
Chasing a personal best. A single fast round is mostly luck. Woods and colleagues found within-person variability of about 40 ms, meaning your own trials scatter that much around your own average without anything changing. If you run twenty times and keep the best one, you are collecting the tail of a distribution and calling it progress. Compare medians across sessions instead.
The thing that looks like improvement but is not
The fastest way to a low number is anticipation — starting the click before the signal appears, timed on the rhythm of the previous rounds. It genuinely produces impressive figures, and it measures nothing. A well-built test defends against this by randomising the delay before the go-signal and voiding any click that lands early, which is what happens on our reaction time test.
Watch for it in yourself. If your score improves sharply while your voided rounds also climb, you are not getting faster; you are gambling more often and being scored on the winning bets. The honest version of the same instinct is useful, though: in real situations, most of what looks like superhuman reaction is prediction. An experienced driver or goalkeeper is not reacting faster, they are reacting earlier because they read the cue sooner.
A sensible routine
If you want a number that improves and means something: sleep properly, test at a consistent time of day when you are reasonably alert, use the same device and input method every time, warm up with two rounds you discard, keep the tab in the foreground, and record the median of a full set rather than your best click. Then look at the trend across a week or two rather than session to session. Most people find that their honest baseline is better than the number that first alarmed them.
Frequently asked questions
Can I actually get faster, or only look faster?
Both, in different amounts. Genuine improvement in simple reaction time is small and plateaus quickly, because the biological floor is close. Recovering avoidable loss — sleep, alertness, warm-up, equipment, technique — is much larger and available to almost everyone. Most reported "improvement" is recovery, and that is still worth having.
Do video games improve reaction time?
Action gamers do tend to score better on speeded visual tasks, but the direction of cause is not settled: fast people may also be drawn to fast games. Where training studies show gains, they are usually strongest on tasks that resemble the game and weaker the further you move away, which is the general pattern for cognitive training.
Does age matter?
Yes, gradually. Simple reaction time slows across adulthood, and the change is steady rather than sudden. It is also smaller than most people expect relative to the variation between individuals of the same age — a well-rested fifty-year-old routinely beats a tired twenty-five-year-old.
How often should I test?
Often enough to have a trend, rarely enough that you are not just practising the test. A few full runs a week under consistent conditions gives you a usable median without turning the measurement into a training exercise.
Why is my phone score different from my computer?
Different display, different input method, different amount of system delay. Touchscreens are generally slower and more variable than a wired mouse. Neither number is wrong; they are simply two different measurement setups, and they should be compared only against their own histories.