Line shuffler

Shuffling a list is useful more often than you might think: randomising quiz questions, choosing a fair presentation order, picking prize winners, mixing test data or avoiding bias in A/B samples. This tool shuffles the lines of any text into a random order, with an optional seed so you can reproduce the same order later.

How to use it

1. Paste a list, one item per line.
2. Optionally enter a seed.
3. Shuffle and copy the result.

Example

Input:

Asha
Ben
Chen
Diego
Ela

One possible shuffle:

Chen
Ela
Asha
Diego
Ben

Why the seed matters

Without a seed, every shuffle is different. With a seed, the same input and seed always produce the same order. That lets you publish the seed with the result so anyone can verify that a draw was not manipulated, or keep a test fixture stable between runs.

How a fair shuffle works

A correct shuffle uses the Fisher-Yates algorithm: walk from the last line to the first, and swap each line with a randomly chosen line at or before it. Every possible order is equally likely. A common mistake in code is sorting with a random comparator, such as sort(() => Math.random() - 0.5), which produces biased results.

Tips

• Remove empty lines first if they should not be shuffled into the list.
• To pick winners, shuffle and take the first N lines.
• For draws that matter, announce the seed method before the draw, not after.