Logical reasoning exercise · ~3 min a run · free
Planning Puzzle
Plan your moves. Zero wasted steps.
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Three pegs hold coloured balls labelled A to D. Rearrange them to match the goal pattern, moving only the top ball of a peg at a time and only if the destination peg has room. Before each puzzle loads, a complete search over all possible arrangements finds the true minimum number of moves needed, so you always know exactly how efficient your solution was, and the level you pick sets how long that shortest solution is.
About this test
About this test
What this test measures
This measures sequential planning and forward-looking working memory: rearranging coloured balls across three pegs to a goal pattern in as few moves as possible, scored against the proven minimum. It rewards thinking several moves ahead and committing to a plan before acting, the core of procedural planning.
How to improve your score
- Plan backward from the goal, find which ball must sit deepest in its target stack and clear whatever is blocking it first.
- Work out the whole sequence in your head before touching a peg, reacting move by move almost always wastes steps.
- Aim for the optimum shown, not just any solution, since every extra move lowers your score for the round.
Good to know
Good to know
Technique: plan backward from the goal
Identify which ball must sit deepest in its target stack, then trace which balls are currently blocking it. Clearing the deepest blocker first often reveals the shortest sequence for the whole puzzle. Pilots who plan 3 or more moves ahead before touching the first peg consistently use fewer total moves than those who react move by move.What a strong score looks like
A session score of 80 or above means you are solving puzzles within 25 percent above the optimal move count on average. Reaching 90 or higher requires near-perfect solutions on most rounds, which means identifying the full sequence before starting. The three levels are set by how long the shortest solution is: 2 or 3 moves at easy, 4 or 5 at medium, and 6 to 8 at hard. On a 7-move puzzle, one wasted move scores 7 divided by 8, which is 88 percent of the round, and two wasted moves score 7 divided by 9, or 78 percent.
Frequently asked questions
How is the optimum move count calculated?
How is the optimum move count calculated?
What happens if I take more moves than the optimum?
What happens if I take more moves than the optimum?
Is this the Tower of London test used in pilot selection?
Is this the Tower of London test used in pilot selection?
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