List Randomizer

A list randomizer takes a list of items — names, numbers, products, prompts — and reorders them unpredictably, picks a subset randomly, or splits them into evenly-sized groups. Teachers use it to group students for an activity; content managers use it to pick a weekly featured post from a backlog; community managers use it to draw giveaway winners; coaches use it to make fair team assignments; DnD dungeon masters use it to pick random encounters from a list. Whenever you need fairness and do not want to be accused of cherry-picking, an unbiased randomizer is the right tool.

The shuffle algorithm matters more than you might expect. Naive approaches like list.sort(() => Math.random() - 0.5) produce badly biased orderings — early items tend to stay near the start and the distribution of outputs is not uniform. The Fisher-Yates shuffle (also called the Knuth shuffle) is the correct algorithm: for each position from the end of the array backwards, swap with a random earlier position. It produces every permutation with exactly equal probability, provided the random number generator itself is unbiased.

This tool uses crypto.getRandomValues, the browser's cryptographically-secure random number generator. That is overkill for sorting a classroom into study pairs, but it matters for giveaways, raffles, and any case where a sceptical observer might ask how the randomness was generated. Math.random is a pseudo-random generator that can be predicted if you know enough consecutive outputs; crypto.getRandomValues is seeded from OS entropy sources and is suitable for cryptographic applications. For legal raffles, many jurisdictions require "verifiable" randomness; check your local rules and document your process if you're drawing prizes with real value.

Three modes cover most workflows. Shuffle all reorders every item — the right choice for playlists, study materials, or breaking up an alphabetical bias. Pick winners draws N items without replacement — the right choice for a giveaway where the same person cannot win twice. Split into groups round-robin deals items into N equally-sized buckets — the right choice for team assignments or dividing up a reading list across students.

Two quality-of-life options. Remove duplicates deduplicates the input before shuffling, which you want for entry lists where someone may have entered twice. Ignore empty lines silently discards blank rows, which is what you want when pasting from a spreadsheet that had trailing blank rows.

Privacy is total: the items never leave your browser. That matters for private lists (candidate names during a hiring round, sensitive client names, embargoed product releases) where pasting them into a third-party service would be a leak risk.

1. Paste your items. One per line, or comma-separated — both work.
2. Pick a mode. Shuffle all, pick N winners, or split into N groups.
3. Set N if needed. Number of winners for pick mode; number of groups for split mode.
4. Shuffle. Results appear instantly. Click "Shuffle again" for a fresh draw.
5. Copy the result. One click to clipboard, formatted for pasting into chat, email, or a spreadsheet.

• Three modes: shuffle all, pick N winners, split into N groups.
• Cryptographically secure Fisher-Yates shuffle.
• Deduplicate and ignore-empties options.
• Accepts newline- or comma-separated input.
• One-click copy of the result in a readable format.
• Runs entirely in your browser — perfect for sensitive lists.