Ladder game

Also called Ghost Leg or Amidakuji. For 2 to 30 people.

Ladder settings

Bottom rowOne per line. Fewer items than people leaves the rest blank.

Rungs

Press Make ladder. The rungs stay hidden until someone goes down.

The link includes your list.

How does it pick? It uses your browser’s cryptographic random numbers, and your list never leaves this device. See how picks are made

How to use it

Names from your list sit along the top. Type what goes along the bottom, one item per line, for example Winner or a chore. If you give fewer items than people, the rest are left blank. Press Make ladder, then tap a name to follow that person’s path down, or press Show all results.

Why the bottom row is shuffled

A plain ladder is not as random as it looks. With the usual number of rungs, a person tends to end up close to where they started. In our own runs with 8 people and a medium ladder, the person on the far left landed directly below their start 24.8% of the time, when a fair draw would give 12.5%.

So this tool shuffles the bottom row first and then builds the ladder. With that step every person is equally likely to get every result, however few rungs there are. The guide has the numbers.

What the ladder guarantees

Every ladder gives each person exactly one result and each result to exactly one person. Two rungs never meet the same upright at the same height, so each path is unambiguous. These rules are checked by automated tests on thousands of generated ladders.

Questions

Why is the limit 30 people?

Beyond 30 uprights the ladder is too narrow to follow on a screen. For bigger groups, the name picker draws winners or an order from a list of any length.

Can other people check the result later?

Yes. Copy result link stores the names, the bottom row and the seed in the address. Opening it rebuilds the same ladder with the same results.

Same list, another way

WheelSpin a wheel of the names Name pickerDraw several names, deal slips or set an order Team generatorSplit the list into even teams

Guides

Is an online wheel spinner really random?Three things decide whether a wheel spinner is fair: where its random numbers come from, how they are turned into a slot, and whether the animation decides anything. Here is how Pickboard handles each.
How to pick winners from a list without repeatsA short, checkable way to draw several winners from a list: clean the list, draw once, keep alternates, and share a link that replays the result.
Ladder lottery (Ghost Leg): how it works and how fair it isA ladder lottery always gives everyone one result, but with a normal number of rungs people tend to land near where they started. We measured how much, and what fixes it.