Does 500Hz Actually Improve Your Reaction Time? The Input-Lag Truth
Quick answer: A faster monitor genuinely lowers your measured reaction time, but mostly by cutting input lag, not by improving your biology. On a 500Hz display the cue reaches your eyes sooner than on a 60Hz one, shaving real milliseconds. Measure yours on the reaction time test and take several runs.
What your reaction score actually contains
When you click on a reaction test, the number you see is your biological reaction plus system input lag — the delay added by the monitor's refresh rate, the mouse and processing. A 60Hz screen can add meaningful milliseconds compared with a 144Hz or 500Hz one, simply because it shows the cue less often. So the same person can post a faster time purely by using better gear.
Why the top of the range is diminishing returns
Going from 60Hz to 144Hz removes a chunk of that lag and is very noticeable. Going from 240Hz to 500Hz removes far less, because the per-frame time is already tiny. For measured reaction time, the biggest wins come from escaping low refresh rates, not from chasing the very highest ones.
The part that is actually you
Your true reaction speed has a firm ceiling — the fastest genuine visual reactions sit just under 150ms, and anything much under 120ms usually means you anticipated rather than reacted. What you can train is consistency, alertness and anticipation, plus stripping out avoidable lag. Sleep and a warm-up move the needle more than any single setting.
Test on consistent gear
Because equipment affects the score, compare like with like: run the reaction time test on the same setup over time rather than comparing across machines. Our guide on how to improve reaction time covers both the training and the lag-reduction side.
Sources: NVIDIA — Reflex · MDN — requestAnimationFrame()
Frequently asked questions
Does a higher refresh rate actually improve my reaction time score?
It improves the measured score, because that number is your biological reaction plus system input lag. A 60Hz screen adds meaningful milliseconds compared with a 144Hz or 500Hz one, simply because it shows the cue less often.
Is 500Hz worth it over 240Hz for reaction time?
The returns diminish sharply. Going from 60Hz to 144Hz removes a chunk of lag and is very noticeable; going from 240Hz to 500Hz removes far less, because the per-frame time is already tiny.
What is a genuinely fast human reaction time?
The fastest genuine visual reactions sit just under 150ms. Anything much under 120ms usually means you anticipated rather than reacted.
How does frame generation affect input lag?
Generated frames do not advance the game state, so latency tracks the internal render rate rather than the counter. The remaining penalty is roughly 8 to 12 milliseconds — comparable to the gap between a 144Hz and a 240Hz display, and larger than the gap between 1000Hz and 8000Hz mouse polling.
Frame generation sits in the same latency budget
The latency arithmetic in this article now has a second variable that did not apply when it was written. Generated frames do not advance the game state, so input latency tracks the internal render rate rather than the number on the counter. NVIDIA Reflex is mandatory with frame generation and offsets part of the cost; published measurements put the remaining penalty at roughly 8 to 12 milliseconds in most games, and that penalty does not grow as the multiplier rises from 2x to 4x.
Put beside the other figures here, 8 to 12ms is a large number. It is comparable to the difference between a 144Hz and a 240Hz display, and larger than the gap between a 1000Hz and an 8000Hz polling rate. If you are spending money to reduce input lag, turning frame generation off in competitive titles is free and larger than most hardware upgrades.
The useful mental model: frame generation buys smoothness with latency, and high refresh rate buys both but only if your render rate keeps up. They are not interchangeable, and the FPS counter does not distinguish between them.