Guides

• ⏲Is an online reaction time test accurate?Where the extra 80 ms comes from, and what we measured building this.measurement~7 min
• ↗How to improve your reaction timeWhat works (sleep, timing, warm-up, hardware) and what does not.practice~7 min
• ⚖Do brain training games actually work?Near transfer, far transfer, and why this site measures instead of trains.evidence~8 min
• ≶What is a good reaction time?Every score from under 150 to over 360, on the screen scale and the lab scale, with the badge each one earns.scores~9 min
• ⌛Average reaction time by ageLab studies say 0.55 ms a year, browser data says 7. Why both are right, and what to expect at your age.age~7 min
• ⇄Reaction time on a phone vs a mousePhones add 35 to 140 ms of screen and touch delay. Which score to trust, and how to compare fairly.devices~6 min
• ⌫How we screen leaderboard nicknamesA slur got through our filter. What replaced it, and why over-blocking costs more.moderation~8 min

Why these exist

A test result on its own invites the wrong conclusion. Two hundred and eighty milliseconds sounds slow next to a published average of 231. But part of that number has nothing to do with you.

• A browser adds roughly 80 ms on its own.
• A 60 Hz screen costs about 5 ms more than a 144 Hz one.
• Your own trials scatter by around 40 ms anyway.

Once you know that, the same 280 looks very different. The guides give each number its context, even the parts that make our own numbers look less impressive.

Every fact here either comes from a named source or was measured by us while building the tests, and where we measured it ourselves the page says so. If something is wrong, write to ysc9550@gmail.com and we will fix it. Want a number first? Start with the reaction time test or the Full Brain Test.

How to use these alongside the tests

We suggest you take a measurement first, then read. With your own median and the spread of your five rounds in front of you, the guides stop being abstract. The line that one person's trials swing by around 40 milliseconds stops being a statistic. It explains the run you just did. Start with the reaction time test, which takes about thirty seconds, or the full brain test, which covers five brain areas in one run.

Before you compare yourself with anyone, read the measurement guide. It changes how you read every other number on the site. It explains why the figure on your screen is not the figure in your nervous system. It also explains why a laptop result and a desktop result are two different measurements, not two tries at the same one.

If your score let you down, read the practice guide before you decide you are slow. Most of the gap between a bad run and a good one comes from sleep, time of day, warm-up and equipment. None of that is fixed about you, and all of it is in your control.

The evidence guide is the sceptical one. It explains why we call this site a measurement tool and not training. It also shows what the research really supports when someone tells you a game will make you sharper.

Which guide answers what

Each of the seven guides answers a different question. If you came here with one of these in mind, go straight to that guide.

• "Why is my number so different from the one in the study?" The measurement guide takes the chain apart: the screen, the mouse, the operating system, the browser event loop. It also shares what we measured ourselves while building this, including the timing bug that made our own early numbers wrong.
• "Can I actually get faster?" The practice guide separates what moves your score from what only sounds like it does. Sleep and time of day move it. Hardware moves it. Most of what gets sold to gamers does not.
• "Will doing this make me smarter?" The evidence guide questions the claims of our own kind of product. Practising a test makes you better at that test. Whether anything spreads beyond it is still argued over, and we would rather say so than sell you a training plan.
• "Is my number good?" The guide to what a good reaction time is puts every reaction time from under 150 to over 360 in one table. It explains why lab averages read about 80 ms faster than the screen, and it answers the 186, 200, 213, 250 and 300 questions one by one.
• "How much slower will I get?" The guide to reaction time by age puts six studies in one table, from 0.34 to 7 ms per year. It explains why lab and browser data disagree by ten times without either being wrong.
• "Why is my phone score worse than my laptop score?" The phone vs mouse reaction time guide takes the touchscreen chain apart. It puts the measured 35 to 140 ms of phone hardware delay next to the desktop figure, and explains why you should never compare the two histories.
• "Who is watching the leaderboard?" The moderation guide explains how nicknames are screened and why blocking too much is the more expensive mistake. It also names the tricks we chose to leave open.

Three things we will not do here

We will not publish a number without saying where it came from. Every figure in these guides either comes from a named peer-reviewed source or was measured by us while building the tests. The ones we measured ourselves are labelled as ours, not dressed up as research. The full source list is on the methodology page.

We will not tell you that repeating these tests will improve your cognition. The evidence does not support it. What repetition does reliably is make you better at these particular tests. Keep that in mind when you look at your own history and see a steep early climb.

We will not rank unlike results together. Every game and difficulty has its own board, and aim has separate mouse and touch boards. Every entry also shows whether it was played by mouse or touch. Still, we think the most reliable comparison is with your own last run.