MLB Chaos Index
The Chaos Index answers one question: how many MLB teams are running a meaningfully different season than last year? The higher the number, the more the league is diverging from its own recent script.
What is the MLB Chaos Index?
The Chaos Index counts how many of the 30 MLB teams are tracking 5 or more wins ahead or behind their pace at the same point last season. A team with 42 wins through 65 games this year, when they had 35 wins through 65 games last year, is in "chaos" — their season is following a different trajectory than before.
When the Chaos Index is high, the current season is particularly unpredictable based on last year's results. When it is low, most teams are running close to their prior-year script — meaning the standings are more predictable.
Which MLB teams are most chaotic compared to last season?
Track The Season's Chaos Report shows the full breakdown: which teams are surging ahead of last year's pace, which are falling behind, and how volatile the current season is overall. The Daily Pulse shows the overnight Chaos Index movement — how many teams entered or left chaos territory since yesterday.
How is the Chaos Index calculated?
For each team:
- Fetch the team's win total through the current number of games played
- Fetch the team's win total through the same number of games last season
- Calculate delta = current wins minus prior-season wins at the same point
- If |delta| ≥ 5, the team counts toward the Chaos Index
The Chaos Index is the total count of qualifying teams. Updated automatically after every completed regular-season game using the MLB Stats API.
Which MLB teams are most chaotic this season?
This changes every day as games are played. Track The Season's Chaos Report shows a live ranking of the teams with the largest positive and negative deltas — the biggest surgers and the biggest sliders.
Why the Chaos Index matters
Traditional standings only show where teams are today. The Chaos Index shows how many teams are in uncharted territory relative to their own recent history. A team at .500 might be dramatically outperforming expectations if they were 10 games under .500 at this point last year. The Chaos Index captures how much of that is happening simultaneously across the league.