Benchmento is a small, independent site hosting short tests that measure reflexes, motor speed and working memory. It exists because the standard versions of these tests are usually a white page with a blue button, and because a raw score with no comparison attached is not very interesting.
How the tests are measured
Every test runs entirely in your browser using the high resolution timer available to JavaScript. Nothing is timed on a server, so network latency never enters a result. What does enter a result is your own hardware: display refresh rate, input device polling, and browser scheduling all contribute a small and mostly constant offset. This is why the reaction time test averages five attempts instead of reporting a single click.
Where the percentiles come from
Each test carries a distribution curve assembled from published ranges for that task, anchored at a series of score and percentile pairs with linear interpolation between them. The percentile answers what proportion of the general population you would expect to beat. It is not a ranking against other visitors to this site, who are a self-selecting group and would produce a misleading comparison.
These curves are indicative rather than clinical. They are good enough to tell you whether you are above or below typical, and not precise enough to distinguish the 71st percentile from the 74th.
Your data
There are no accounts and no score uploads. Personal bests, streaks and half-finished puzzles live in your browser's local storage on the device you played on, and you can see all of it on your bench.
Two things follow from that, and both are worth knowing. Clearing site data clears your scores. And Safari on iPhone and iPad deletes local storage for sites you have not visited in about two weeks, so a long gap can wipe your record even if you never cleared anything yourself. Your bench has an export button that saves everything to a file, and an import button to restore it here or on another device. That file is the only backup that exists.
Supporting the site
Benchmento is free and has no paid tier. It is funded by advertising placed well away from anything you click during play, and by people who choose to buy the developer a coffee. Neither affects what the tests measure or what they report.
Corrections
If a score curve looks wrong, a test misbehaves on your device, or a page has an error in it, the contact page is the place to say so. Bug reports that include your browser and device are the most useful kind.
If you came here from Human Benchmark, the comparison page says what is the same and what is not.
Who runs this
Benchmento is an independent site built and maintained by one person. It is not a laboratory, not a research group, and not affiliated with Human Benchmark, RapidTables, or the Kyoto University Primate Research Institute. Where a task here resembles one of theirs, that is because the task itself is a public measure rather than anyone's property.
Simple visual reaction time, digit span, spatial span and the numeral task the chimp test is based on have been used in psychology for decades and are described in published literature. What belongs to this site is the implementation: the copy, the scoring curves, the percentile model, the shape generator behind Split Test and Balance Point, the daily puzzles, and the challenge links. Those were written here.
What happens to your results
Nothing is uploaded. Every score, streak and unfinished puzzle is written to your browser's local storage on the device you played on. There is no account to create, no server holding a copy, and no public leaderboard. Your bench shows everything the site holds about you, and there is one button to export it to a file and another to delete all of it.
The percentiles come from published score distributions for each task rather than from other people who used this site. Ranking you against visitors to a reflex-testing website would compare you to a self-selected group that is faster than the general population, which makes the number mean less rather than more.
Money
The site is free and carries advertising to cover hosting. Ads never sit next to a click target during play, because an accidental click on an advert beside a CPS pad is invalid traffic and helps nobody. There is a donation link for anyone who wants to use it, and nothing is behind it.
The card and table games use free chips. There is no deposit, no purchase, no prize and no cash-out anywhere on the site, and nothing here can be exchanged for money or anything of value. The chips are a score. These are not real-money gambling and no gambling licence applies to them. The site is intended for an adult audience and we suggest 18 or over.