Amidakuji (Ladder Lottery Generator)
FreeGenerate a random, fair "ghost leg" ladder lottery (amidakuji) that pairs participants with outcomes one-to-one. Trace each line down the ladder to reveal results, or show them all at once.
Runs entirely in your browser. Nothing is uploaded, and results are never shown to other visitors unless you share the link yourself.
Revealed Results
Click a participant above the ladder to reveal their result.
What this tool does
Amidakuji (Ladder Lottery Generator) builds a random "ghost leg" ladder that pairs a list of participants with a list of outcomes one-to-one and fairly. Type in names and optional outcomes, generate a ladder, then click each participant to watch their line trace down through the ladder's rungs to reveal what they got, or reveal everyone at once.
How It Works
The ladder is a grid of vertical lines (one per participant) crossed by horizontal rungs placed at random rows. Tracing any line from top to bottom, every time it meets a rung it jumps to the neighboring line before continuing down -- exactly like following a single wire through a tangle. Mathematically, each rung is a transposition (a swap of two adjacent positions), and a chain of transpositions is always a bijection: every top position ends up mapped to exactly one bottom position, and no two participants can ever land on the same outcome.
Rungs are generated row by row: for each row, the tool scans left to right and randomly decides whether to place a rung between each pair of neighboring lines, skipping the next position whenever a rung is placed so that no vertical line is ever asked to jump twice in the same row. The "Rung Density" setting only changes how likely a rung is at each position (roughly 30% for Sparse, 45% for Normal, 65% for Dense) -- it changes how tangled the ladder looks, not how fair the result is.
Problems it solves
- Assigning people to tasks, teams, seats, or turns without any argument about who picked what.
- Running a classic Japanese-style ladder lottery for a game, stream, classroom, or office game, with a visual reveal everyone can watch.
- Deciding a single winner (or loser) out of a group fairly, with one outcome set to "Win" and the rest left as "Lose".
- Sharing the exact same unrevealed ladder with a remote group via a link, so everyone reveals their own result independently.
Frequently asked questions
›Is every participant equally likely to get any outcome?
Yes. Each ladder is a chain of random swaps (rungs) between neighboring lines, and the composition of any number of swaps is always a one-to-one mapping -- every participant ends up connected to exactly one outcome, and every outcome is reached by exactly one participant. Adding more rungs (a denser ladder) just makes the path look more tangled; it doesn't change the odds.
›Can I reuse the exact same ladder later, or share it with the group?
Yes. Click Share Link after generating a ladder -- it copies a URL that encodes the participants, the outcomes, and the ladder's random seed, so anyone who opens it sees the identical, unrevealed ladder. Nobody's individual result is included in the link unless you reveal it first and send that separately.
›What happens if I list fewer outcomes than participants?
The missing slots are automatically filled with "Lose", so you only need to type the outcome(s) that matter (like a single "Win") and leave the rest blank. If you list more outcomes than participants, the extra ones are simply ignored.
›Why trace the lines down one at a time instead of just showing a list of pairs?
Tracing the path is the whole point of amidakuji (literally "ladder lottery" in Japanese): it lets a group watch the result unfold visually and confirms nobody picked their own outcome in advance. Use Show All Results instead if you just want the final pairing without the reveal animation.
›Is this the same thing as "ghost leg" or "ladder lottery"?
Yes, those are the common English names for amidakuji (阿弥陀籤), a traditional Japanese method for making a random, fair assignment between two equal-sized lists -- used for everything from choosing who buys lunch to splitting up chores.
Related Tools
Game
Bingo Card Generator
Generate unique, print-ready 5x5 bingo cards with classic 1-75 numbers, custom words, or emojis, in a choice of color themes.
FreeGame
Click Speed Test (CPS Test)
The classic click test: click as fast as you can for 1 to 100 seconds with Left Click, Right Click, or Spacebar modes. Tracks your personal best for each mode and duration, your best 1-second burst, and gives you a rank title from Turtle to Godlike Clicker.
FreeGame
Spin the Wheel (Wheel of Names)
Turn any list into a spinning wheel and get a fair random pick in seconds. Free, no sign-up, everything runs in your browser.
FreeGame
24 Game Solver & Trainer
Solve the classic 24 Game instantly, or practice against the clock with an auto-generated, guaranteed-solvable puzzle and live scoring. Free, private, runs in your browser.
Comments (0)
Found this tool useful? Leave a comment, share a tip, or tell us how we can make it better.
No comments yet. Be the first to share your thoughts!