One solid built from cubes at the top, four below. Exactly one of the four is the top shape rotated; the rest are mirror images that never line up however you turn them. Rotate it in your head and pick.
The task from the psychology textbooks
This is mental rotation, built by Shepard and Metzler in 1971. When people were shown two solids and asked whether they matched, the time they took was directly proportional to the angle between them — famous evidence that we really do turn objects in our minds. It became the standard measure of spatial ability.
The mirror images are the point. Your left and right hands never superimpose no matter how you rotate them, and the wrong answers here have exactly that relationship — so "looks about right" gets you caught.
| 30 or more | You have a 3D viewer in your head |
|---|---|
| 22–29 | Top tier |
| 15–21 | Strong spatial sense |
| 9–14 | Above average |
| 4–8 | Average |
How to play
- Press START: the blue reference solid appears on top, four lime options below.
- Pick the option that rotates into the reference shape.
- Correct and you move straight on. Wrong or out of time costs a heart, and the correct option turns to the reference angle so you can see what was different.
- Three hearts gone and you reach the result. Your score is the number you got right.
The clock
The first question gives you 20 seconds, and every question after that is 0.7 s shorter, down to a floor of 8 seconds — reached around question seventeen. Early on you can afford to rotate the whole thing; later you have to switch to reading the key features at a glance.
Tips
- Do not rotate the whole solid. The two short tails carry almost all the information. Use the long bar as your reference and compare which way each tail bends.
- Right-hand rule. Grip the long axis with your thumb and the first bend with your index finger; where the remaining bend points sorts mirrors out immediately.
- Counting cubes is useless — every option has the same ten. Look at the spacing between bends (two cubes or three) instead.
Scoring and the leaderboard
Your score is the number answered correctly, higher is better. Every question is generated fresh (a ten-cube shape folded at random, discarding any shape symmetric enough to match its own mirror) and the options are reshuffled, so memorising or screenshotting gets you nowhere. One correct answer is enough to post, one row per account.
Frequently asked questions
Is there really only one correct option?
Yes. Each generated question is checked by matching all four options against the reference through the 24 axis rotations, and it is only used when exactly one matches. The three wrong ones are two mirrors plus one shape with a single cube moved — if all three were mirrors you could pick by spotting the matching trio.
Is spatial ability innate?
It trains. Repeated practice reliably improves mental rotation in studies, and the commonly reported gender gap narrows with training too. A few days on this and you will see your score climb.
The shapes are too small on my phone
They scale with the screen width. Turning the phone landscape puts all four options in one large row.
Related tests
- Ball Tracking Test — holding several things at once
- Sequence Memory Test — remembering positions
- Minesweeper — spatial deduction
- N-back Test — working memory