Games
Fifteen quick browser games. Most measure something real — how fast you type, how quickly you react, how much you can hold in your head — and two of them you play against your friends live, by sharing a code. Every best score is saved on your own device, with no account and no leaderboard full of strangers.
Flagship
Darts 301
Up to five players on one board. Share a room code, throw from your own phone, and watch every score, bust and checkout land live.
👥 Play with friends
Share a code and play together, live, from wherever you are.
⚡ Speed and reflexes
How fast can you react, click and aim?
Measure your WPM and accuracy in 12 languages.
How fast are your reflexes? Measure it in milliseconds.
Hit 30 targets as fast as you can.
How many clicks per second can you manage?
🧠 Memory
How much can you hold in your head at once?
Repeat a growing sequence. How many can you hold?
A number flashes up. Type it back.
Squares flash on a grid. Tap them all back.
Click the numbers in order — after they vanish.
👁️ Focus and perception
Attention, colour discrimination and cognitive control.
🧩 Puzzles and words
Slower games for when you want to think rather than twitch.
Why these games?
Each one does a real, repeatable thing, and works the same on a phone as on a laptop. The typing test gives you a number you can actually train against, and Typing Battle turns that number into a race. The reaction test uses the browser’s high-resolution clock rather than a rough timer. The memory game maps neatly onto the classic research on short-term memory span. And Darts 301 is a proper game of 301 — busts, doubles, checkouts — for up to five people who only need to share a five-character code.
Are the scores stored anywhere?
Only in your own browser. Personal bests live in localStorage on the device you played on, and you can wipe them at any time from the privacy page. DO101 does not run a leaderboard, so there are no invented high scores to chase.