Why do I test faster on solo sites than in duels?

No pressure and cherry-picked singles. Duel averages include your nerves — which is precisely why they're the more honest number.

Which test should I use to track progress?

Any one, consistently — same site, same device, ten-round averages weekly. Cross-site comparisons wobble by 10–20 ms due to timing implementations.

Are browser reaction tests accurate?

Accurate enough for tracking: input and display latency add a device-specific constant, which cancels out when you compare your own scores over time.

Reaction time test sites, compared honestly

Search "reaction time test" and you'll meet three species: the big benchmark suites (Human Benchmark and kin), the single-widget test pages (click-when-green in a frame of ads), and duel-based tests like blocks.pw where the measurement runs against an opponent.

What reaction time test sites does brilliantly

Benchmark suites: huge percentile datasets and multiple cognitive tests — the reference numbers everyone quotes.
Widget pages: fastest possible path to a rough number, no frills.
Lab-grade tools (research software): millisecond-precise hardware timing — for actual science, not fun.

What blocks.pw does differently

The duel format measures reaction under pressure — the version of your speed that actually shows up in games, sports and traffic. Solo tests flatter everyone by 10–20 ms.
Averages by design: Reflex duels and the Reaction solo mode score across rounds, killing the lucky-single-click problem that inflates solo-site bragging.
Interpretation built in: 260+ pages of verdicts, age curves and percentiles turn your milliseconds into meaning — most test sites hand you a number and a shrug.
A reason to return: ELO and country leaderboards make speed a rank you maintain, not a one-off screenshot.

Side by side

	reaction time test sites	blocks.pw
Best for	Reference percentiles (suites)	Contested, ranked measurement
Pressure	None — solo	Real opponent, real stakes
Scoring	Single attempts or averages	Best-of-5 duels + averaged solo runs
Interpretation	A chart, sometimes	Verdict pages for every ms and age
Retention	Screenshot	ELO + country leaderboards

Which should you use?

Want the canonical percentile chart? Benchmark suites. Want a number in nine seconds? Any widget. Want your reaction time to mean something — measured under pressure, averaged honestly, ranked against your country — that's the duel format. Test everywhere; compete where the scoreboard remembers.

The blocks.pw side of the table in one paragraph: 30-second best-of-5 duels, free, no account, no install, challenge links + country elo leaderboards — nine duel mini-games plus solo world records, built to settle things. Judge it in one quick match; it takes less time than reading this sentence took.