Hold the green dot and trace a winding path to the end. You only move forward while inside the path, and the whole run shares 2.4 seconds of wall time

How to use it

1. Press START and level 1 opens: a green dot marks the start, a red GOAL the end. In portrait the path runs top to bottom, in landscape left to right.
2. Press the green dot and keep holding — mouse button down, or finger on the glass — while you follow the path. Your marker is green inside the path and turns red on the wall, with a red flash and "Wall!" at the bottom.
3. The top row shows the current level and the percentage of time spent inside the path; the bar under it is your remaining wall budget, running green → yellow → red. The part you have covered is tinted green.
4. Reach the GOAL and "CLEAR!" hands you the next level plus 0.5 seconds of budget back. Each level is narrower, and the shape is generated fresh every time.
5. Run the budget down to zero and the result screen shows the level reached, your grade, time inside the path and personal best, with Again, Share result and a nickname field to Submit score. There is no level cap — the path just keeps narrowing.

Rules and scoring

Path width starts at 52 px on a screen whose shorter side is 400 px and drops 15% per level (52 → 44 → 38 → 32 → 27 → 23 → 20 → 17 → 14 → 12…, with 4 px as the floor), scaling with your screen; touch devices get an extra 8 px for the width of a fingertip. The bends stop getting busier at level 9 — after that only the width shrinks.

The wall budget is 2.4 seconds for the entire run. It does not reset between levels: it drains while you are on the wall, and at zero the run ends on the spot. Clearing a level hands back 0.5 seconds, capped at 2.4. Scrape your way through the early levels and there is nothing left for the narrow ones. Letting go is not a game over: "You let go — again" appears and that level restarts, but the budget you already spent does not come back.

You only make progress while inside the path. Once you are on the wall, moving forward does nothing, so you cannot flick across the bends. Judging interpolates every 3 px between frames, so a wall you brushed at speed still counts. Time inside the path is the share of those sample points that were inside, and your final accuracy is the average over the levels you cleared.

The ranked score is levels cleared × 10,000 + accuracy × 100. Five levels at 97.32% gives 59,732; three levels at 92% followed by a failure on level four gives 39,200. Levels come first and accuracy breaks ties down to two decimals, so players on the same level still separate. Clearing no level means no submit form, and one connection can submit five times per minute. Your best stays in this browser, and the share link carries your level and accuracy.

Everyone's hands shake

Even at rest your hands oscillate eight to twelve times a second, far too small to see. That is physiological tremor, and it is normal. Caffeine, lack of sleep, nerves, cold and muscle fatigue all amplify it until it shows. What this test measures is how well you can suppress that tremor at the fingertip — which is why the same person scores differently in the morning and at night, or before and after coffee.

Level 12 · 95%+	Surgeon hands — under 12 px wide, almost untouched
Level 10	Watchmaker hands — only reachable if you saved your budget
Level 8	Steady enough for calligraphy or nail art
Level 6	A typical adult, concentrating
Level 4	Caffeine or nerves are showing
Levels 1–3	Rest day. Sleep and retry

Steady people move from the shoulder

Move only your wrist and one joint carries all the shake. Plant your elbow on the desk and push with the whole arm and the tremor spreads across several joints and mostly cancels out. Surgeons brace their forearms and shooters tuck their elbows for the same reason. Moving on the out-breath helps too — the chest is stiller between breaths.

Finger and mouse are different events

On a phone your finger hides the path ahead and its contact patch is wide, so you touch the wall more. A mouse has the wrist supported on the desk. The leaderboard mixes both, so compare with people on the same kind of device. A tablet with a stylus is the steadiest of all.

If your tremor got worse suddenly

If it persists after cutting caffeine and a night's sleep, affects one hand only, or is worse at rest than in motion, that is a pattern worth showing a neurologist. This test measures fingertip control; it does not tell you why a hand shakes.

Frequently asked questions

Is letting go an instant fail?

No. Releasing restarts only the level you are on. The run ends when the 2.4-second wall budget hits zero. Note that restarting a level does not refill it, so you cannot erase wall contact by lifting off and starting again.

Can I just flick across the bends?

No. Progress only advances while you are inside the path, so racing forward on the wall gets you nowhere. Judging interpolates every 3 px between frames, so fast brushes against the wall still register.

What counts as a good level?

With a mouse, level 6 (23 px) is average, level 8 (17 px) means genuinely steady hands, and above level 10 (12 px) are people who barely spent any budget. At level 12 the path is thinner than 10 px — a line on the screen.

Why does the same level feel harder some days?

Each path is built from overlapping sine waves with a new random seed, so the bends land in different places every run. The width per level is fixed; the shape is not — and your hands vary too.

Related tools

• Perfect Circle Test — the same fine motor control, judged on roundness
• Aim Trainer — speed instead of precision: 30 targets, fast and accurate
• Reaction Time Test — tap the instant the screen turns green