Team Randomizer

What it does

Splitting a group into balanced teams is a recurring problem — pickup basketball, office team-building, classroom group projects, kids' birthday party games, esports scrim partner-up. The naive solution (count off “1, 2, 1, 2”) works for unweighted groups but fails when skill levels vary widely. The two main algorithms for this problem: pure random (Fisher-Yates shuffle, then split — fair in expectation, can produce unbalanced teams by chance), and greedy-balanced (sort by skill rating descending, snake-draft into teams — best #1 to team A, best #2 to team B, best #3 to team B, best #4 to team A — produces near-optimal balance for skill-rated groups).

The randomizer accepts one name per line, optionally with skill rating after a comma (Alice,8 / Bob,5 / Carol,7). Pick number of teams (2-6 typical) and balancing mode (random or greedy-balanced). For greedy-balanced with skill ratings, the algorithm uses the snake-draft approach to minimize total-skill-difference between teams. For pure random, it uses Fisher-Yates shuffle then partitions — every player has equal probability of any team. Re-shuffle unlimited times until the result feels right (sometimes the “fair” algorithm produces a result everyone agrees feels off for non-skill reasons — gender mix, friend groups, prior team experience).

Edge cases worth handling: odd group sizes where teams can't be exactly equal (the tool puts the extra player on a designated team or rotates), strict team-size requirements (“exactly 5 per team” for sports with fixed roster sizes), and locked pairings (these two friends always together, those two siblings on different teams). Most birthday-party and casual-pickup uses don't need locked pairings; structured leagues do. For professional / ranked esports, more sophisticated MMR-balancing tools exist; for everything else, this is enough.

How to use it

1. Paste one name per line. Optionally add comma + skill rating (Alice,8).
2. Pick number of teams (2, 3, 4, 5, or 6).
3. Pick balancing mode: random (pure shuffle) or greedy-balanced (snake-draft by skill).
4. Click Shuffle — copy or screenshot the result.
5. Re-shuffle if the result has obvious imbalance (some randomness can produce uneven teams; greedy-balanced minimizes this).

When to use this tool

• Pickup basketball, soccer, volleyball — quick fair team split.
• Office team-building or trivia night.
• Classroom group projects where mixed-ability is desired.
• Kids' birthday party games (relay races, capture the flag).
• Esports scrim partner-up (5v5, 6v6 team formats).

When not to use it

• Ranked competitive matchmaking — use MMR-based systems with detailed skill metrics, not a generic shuffler.
• Teams with strict role requirements (you need exactly 1 healer, 2 tanks, 5 DPS) — assignment problem, not just split.
• Teams that need to balance gender, age, or other demographics — basic randomizer won't handle this; needs custom logic.
• Long-running league play where team balance accumulates effects across multiple games — accumulated win/loss should weight balancing.

Common use cases

• Onboarding a colleague who needs the same calculation/conversion
• Verifying a number or output before passing it on
• Quick use during a typical workday
• Pre-decision sanity-check on inputs and outputs