Tower of Hanoi 3, 4 or 5 pegs

Click a peg to lift its top disk, then click where it goes. Every position shows exactly how many moves are still needed to stack all disks on the goal peg, and a lifted disk shows what each drop would leave — because your tab has just searched every position. With four pegs this is the only way to know: the Frame–Stewart strategy was proved optimal only in 2014, and the positions farthest from a full tower are not always the tower on another peg.