✨ Dot Blitz
Perception / Speed · Free online · No download · No sign-up
Dot Blitz flashes a cluster of coloured dots on screen for a fraction of a second — just long enough to perceive but far too short to count one by one. Then it asks: how many were there? You pick from multiple-choice answers that include close neighbours of the true count, so wild guessing rarely works. The early rounds use small dot counts and forgiving spreads; the later rounds pile on decoy shapes and pack the dots into clusters that defeat your usual estimation tricks. Dot Blitz is the closest browser game to a clean test of subitising — the brain’s ability to grasp a small number at a glance without counting.
How to play Dot Blitz
- Press Start to begin a round — a flash window appears.
- A cluster of coloured dots is shown for around 900 milliseconds, then hidden.
- Choose the dot count you saw from the multiple-choice options below.
- Higher levels add decoy shapes (squares, triangles) that you must exclude from your count.
- Correct answers score points; wrong answers cost a life and reset your streak.
- Twenty rounds per session — chase the highest final score.
Tips to beat your high score
- Group into threes. Subitising works flawlessly up to about four objects. Beyond that, group the dots into visual triplets and add the chunks: three threes is nine.
- Ignore decoys early. When non-dot shapes are present, scan briefly for their shape before counting. Decoys are usually placed deliberately to trick your grouping.
- Mind the cluster vs spread. Dense clusters feel like fewer items than they really contain; widely spread dots feel like more. Learn your personal bias from misses and correct for it.
- Trust your first impression. The brain forms a count estimate within the first 200 ms. Second-guessing after the flash ends almost always pulls you toward a wrong neighbour.
- Skip recount attempts. Once the dots disappear you cannot recount — the visual trace fades within a second. Commit to your initial impression instead of staring at the now-empty grid.
What this game trains your brain to do
Dot Blitz directly tests subitising, a perceptual phenomenon first described in the 1940s. Subitising is the near-instantaneous knowledge of how many items are present in a small set, without explicit counting. Most adults subitise reliably up to four items; beyond that they switch to counting or estimation. The boundary is biological — the parietal cortex appears to house circuits that encode small numerosities directly, while larger numbers engage a separate approximate number system.
Studies of children show that subitising ability at age five is one of the strongest predictors of later mathematics achievement, far stronger than IQ. Training games like Dot Blitz have been shown to improve numerical fluency in both children and adults, suggesting the underlying perceptual system remains plastic well into adulthood. Adults who play dot-counting games regularly report faster estimation in everyday situations involving quantities.
About Dot Blitz
Dot Blitz is one of the few browser games that targets a specific cognitive mechanism backed by decades of research. The flash time, decoy presence, and cluster spread are all calibrated to gradually push beyond the comfort zone of pure subitising.
All CrizBrain games run entirely in your browser. No account, no install, and your highest score is saved privately on your device. Dot Blitz takes 90 seconds to play through a full session and is one of the most replayable games on the site.