About Teams Generator: How It Works and Who Built It

Teams Generator is a free tool for splitting a list of names into fair, random teams or groups. This page covers who built it, how the randomization actually works, and why you can trust that the results aren’t rigged. If you’ve ever wondered whether a “random” tool is really random, this is the page that answers it.

Who built this

Teams Generator was built by Tim, an independent maker who builds small, focused web tools. You can find more of his work at timmyships.com. The goal here was narrow on purpose: do one job, splitting people into fair teams, better than the ad-cluttered tools that already rank for it.

That means no signup, no upsell, and no wall of ads between you and the result. Paste, generate, done.

For anything about the tool, corrections, or feedback, email info@teamsgenerator.com. Real messages get read.

How the randomization works

The fairness of a team generator comes down to one thing: is the shuffle actually unbiased? A lot of quick-and-dirty tools aren’t. Here’s exactly what this one does.

Every split runs on the Fisher-Yates shuffle, a well-known algorithm that’s been the standard for unbiased shuffling since the 1930s (Ronald Fisher and Frank Yates first described it; Richard Durstenfeld gave it its modern computer form in 1964). In plain terms: the tool walks through your list from the last name to the first, and at each position it swaps that name with a randomly chosen one from the names not yet placed. Done correctly, every possible ordering of your list comes out with exactly the same probability.

That last part matters. Some naive shuffles look random but quietly favour certain orderings. Fisher-Yates doesn’t. There are as many possible outcomes as there are ways to arrange your list, and each is equally likely.

The randomness itself comes from your browser’s built-in random number generator, the same source browsers use for their standard random functions. For share links and reproducible results, the tool can seed the shuffle so a specific link always reopens the exact same teams.

Why the teams come out even

A fair shuffle gives you a random order. Even team sizes come from what happens next: people are dealt out one at a time across the teams, the way you’d deal a deck of cards. First person to team one, second to team two, and so on, cycling back around.

Because of that dealing step, team sizes never differ by more than one person. Ten people into three teams gives 4, 3, and 3, never 6, 2, and 2. When the total doesn’t divide evenly, the leftover people land on the first teams dealt, and the tool tells you how the remainder shook out so nothing’s hidden.

How keep-together and keep-apart fit in

Constraints run before the random fill. If you’ve pinned people to the same team, or forced them onto different teams, the tool places those people first according to your rules, then shuffles everyone else around them. If a rule can’t be satisfied, say you asked to keep six people together but only made teams of four, you get a plain warning instead of a silently broken result. The tool won’t pretend it did something it couldn’t.

Everything runs in your browser

There’s no server doing the work. The whole tool, the shuffle, the team split, the exports, runs as code in your browser on your own device. Nothing you type is uploaded.

That’s a deliberate choice, not just a technical one. When you’re splitting a class of students or a list of staff, those names shouldn’t leave your control. Here, they don’t. Share links carry your list inside the URL itself, so even sharing keeps you in charge of who sees it. The privacy policy spells out exactly what is and isn’t collected (short version: the site uses Google Analytics to count visits, and your list of names is never part of that).

Try it

The fastest way to see it work is to use it. Start with the random team generator on the homepage, or jump to the random group generator if you think in groups. Teachers have a dedicated classroom group generator, and there’s a team name generator for naming whatever you build.