2026 FIFA World Cup Predictions
FiveThirtyEight vs KenPom: Two Methodologies, One Tournament
Problem Statement
The 2026 FIFA World Cup marks a historic expansion from 32 to 48 teams, fundamentally changing tournament dynamics. With the tournament co-hosted by the USA, Mexico, and Canada, fans and analysts alike are asking: Who will win the first expanded World Cup?
We pushed the boundary: What happens when soccer meets college basketball’s most acclaimed rating system*?*
This project implements TWO world-class prediction methodologies:
FiveThirtyEight’s SPI - The gold standard in soccer analytics
KenPom-style ratings - Adapted from college basketball’s most trusted system
Using the actual 2026 World Cup draw and FIFA’s official bracket structure, we simulate the tournament 10,000 times to generate stage-by-stage probabilities.
The Actual 2026 World Cup Draw
Unlike random simulations, we use the official FIFA group assignments:
| Group | Teams |
|---|---|
| A | Mexico, South Africa, Korea Republic, TBD (UEFA Playoff) |
| B | Canada, Qatar, Switzerland, TBD (UEFA Playoff) |
| C | Brazil, Morocco, Haiti, Scotland |
| D | United States, Paraguay, Australia, TBD (UEFA Playoff) |
| E | Germany, Curaçao, Côte d’Ivoire, Ecuador |
| F | Netherlands, Japan, Tunisia, TBD (UEFA Playoff) |
| G | Belgium, Egypt, Iran, New Zealand |
| H | Spain, Cabo Verde, Saudi Arabia, Uruguay |
| I | France, Senegal, Norway, TBD (Intercontinental Playoff) |
| J | Argentina, Algeria, Austria, Jordan |
| K | Portugal, Uzbekistan, Colombia, TBD (Intercontinental Playoff) |
| L | England, Croatia, Ghana, Panama |
Playoff teams are resolved probabilistically based on SPI ratings from the UEFA and Intercontinental playoff pools.
Approach & Methodology
Methodology 1: FiveThirtyEight Soccer Power Index (SPI)
Built from 7,600+ international matches (2018-2025), our SPI system calculates:
Offensive Rating: Expected goals scored vs. average opponent
Defensive Rating: Expected goals conceded vs. average opponent
Overall SPI: Composite strength rating (0-100 scale)
Key model features:
Tournament Weighting: World Cup (1.0x), Euro/Copa América (0.9x), Qualifiers (0.7x), Friendlies (0.4x)
Time Decay: Recent matches are weighted more heavily
Home Advantage: +0.4 expected goals for host nations
Host Boost: Additional +0.3 goals for USA, Mexico, and Canada in their matches
Methodology 2: KenPom-Style Ratings (Adapted for Soccer)
Inspired by Ken Pomeroy’s college basketball rankings, we built a soccer adaptation featuring:
Iterative Opponent Adjustment: 50 iterations of strength-of-schedule correction
Adjusted Offensive Efficiency (AdjO): Goals scored, adjusted for opponent quality
Adjusted Defensive Efficiency (AdjD): Goals conceded, adjusted for opponent quality.
Tempo Factor: Accounts for pace of play differences between teams
Pythagorean Expectation: Win probability derived from goal differential (exponent: 1.3)
Key Difference: KenPom uses iterative convergence to estimate teams' underlying strength, seeking stable ratings, while FiveThirtyEight’s SPI adjusts ratings incrementally with each new match result.
The Actual FIFA Bracket Structure
We implement the official Round of 32 bracket with exact matchups:
Round of 32 (sample matchups):
Match 73: Runner-up A vs Runner-up B
Match 76: Winner C vs Runner-up F
Match 74: Winner E vs Best 3rd (A/B/C/D/F)
...
Round of 16:
Match 89: Winner of M74 vs Winner of M77
Match 90: Winner of M73 vs Winner of M75
...
This means bracket positioning matters—being in Group C vs Group J affects your path to the final.
Monte Carlo Tournament Simulation
Both systems fuel the same simulation engine: 10,000 tournaments, each decided by Poisson-powered goal scoring:
Each simulation:
Resolves playoff TBD slots probabilistically
Plays all 144 group stage matches
Ranks groups and selects the 8 best 3rd-place teams.
Follows the actual FIFA bracket through knockouts
Tracks every team’s advancement at each stage
Key Findings
Championship Predictions: SPI vs KenPom
| Rank | Team | SPI Win % | KenPom Win % | Agreement |
|---|---|---|---|---|
| 1 | Spain | 10.2% | 9.8% | ✓ Strong |
| 2 | France | 8.4% | 7.6% | ✓ Strong |
| 3 | Argentina | 7.1% | 8.3% | ✓ Strong |
| 4 | England | 6.8% | 5.9% | ✓ Strong |
| 5 | Brazil | 5.9% | 6.4% | ✓ Strong |
Both models make one thing clear: Spain leads the pack, yet the revamped format keeps every side’s dreams alive—no team has more than an 11% shot.
Where the Models Diverge
| Team | SPI Win % | KenPom Win % | Difference |
|---|---|---|---|
| Argentina | 7.1% | 8.3% | KenPom +1.2% |
| Netherlands | 4.8% | 3.5% | SPI +1.3% |
| Germany | 5.2% | 4.1% | SPI +1.1% |
KenPom tends to rank teams higher when they show strong underlying metrics, such as Argentina’s high Pythagorean expectation, due to its iterative adjustment process. SPI gives more weight to teams with recent strong performances, like Germany’s recent Nations League results, since it relies on continually updated match data.
Host Nation Outlook (With Actual Groups)
| Host | Group | SPI Win % | KenPom Win % |
|---|---|---|---|
| United States | D | 4.2% | 3.8% |
| Mexico | A | 2.8% | 2.5% |
| Canada | B | 3.1% | 2.9% |
The United States has the best draw among hosts—Group D (Paraguay, Australia, TBD) is more favorable than Mexico’s Group A or Canada’s Group B with Switzerland.
“Group of Death” Analysis
| Rank | Group | Avg SPI | Teams |
|---|---|---|---|
| 1 | Group L | 78.4 | England, Croatia, Ghana, Panama |
| 2 | Group H | 76.2 | Spain, Uruguay, Saudi Arabia, Cabo Verde |
| 3 | Group I | 75.8 | France, Senegal, Norway, TBD |
England and Croatia face the toughest path out of the groups.
Bracket Positioning Impact
Comparing the random bracket vs. the actual FIFA bracket reveals significant differences:
| Team | Random Bracket | Actual Bracket | Impact |
|---|---|---|---|
| Portugal | 4.8% | 5.9% | +1.1% (favorable draw) |
| Germany | 5.8% | 5.2% | -0.6% (tough bracket half) |
| Argentina | 7.5% | 7.1% | -0.4% (slightly harder path) |
Model Validation: 2022 World Cup
We validated both models against the 2022 Qatar World Cup using pre-tournament data:
| Metric | FiveThirtyEight SPI | KenPom-Style | Winner |
|---|---|---|---|
| Championship MAE | 0.0312 | 0.0298 | KenPom ✓ |
| Round of 16 MAE | 0.0845 | 0.0821 | KenPom ✓ |
KenPom slightly outperformed SPI on both metrics, suggesting the iterative opponent-adjustment methodology better captures true team strength.
Both models correctly identified Argentina and France as top contenders, and flagged Morocco as an underrated dark horse.
What Makes This Project Unique
Actual Tournament Structure: Uses real 2026 groups and bracket
Dual Methodology Comparison: First-ever FiveThirtyEight vs KenPom for soccer
KenPom Soccer Adaptation: Novel application of basketball’s #1 rating system
Bracket Position Analysis: Quantifies how draw luck affects championship odds
Rigorous Backtesting: Validated against 2022 World Cup actual results
FiveThirtyEight-Quality Visualizations: Publication-ready charts with official styling
Technical Implementation
Data Pipeline
VIRTUAL_HACKATHON.SOCCER_DATA.RESULTS (48,000+ matches)
↓
Historical Name Mapping (USSR → Russia, etc.)
↓
Tournament Weighting + Time Decay
↓
┌─────────────────┬─────────────────┐
│ FiveThirtyEight│ KenPom-Style │
│ SPI Ratings │ AdjO/AdjD │
│ (incremental) │ (50 iterations)│
└────────┬────────┴────────┬────────┘
↓ ↓
Playoff Resolution (TBD teams)
↓ ↓
Actual FIFA Bracket Structure
↓ ↓
Monte Carlo Simulation (10,000x)
↓ ↓
Stage-by-Stage Probabilities
Tech Stack
Data: Hex SQL connection to Snowflake
Modeling: Python (NumPy, Pandas, SciPy)
Visualization: Matplotlib + Seaborn (FiveThirtyEight style)
Simulation: Poisson-based Monte Carlo with actual bracket logic
Limitations
Playoff uncertainty: 6 teams still TBD from UEFA/Intercontinental playoffs
No roster data: Models use team-level results only; injuries and squad changes aren’t captured
Manager effects: Tactical changes from new coaches aren’t explicitly modeled
Friendly match noise: Even with 0.4x weighting, friendlies can distort ratings
Historical bias: Teams with fewer recent matches have more uncertain ratings
Conclusion
Our dual-methodology analysis exposes a wild, unpredictable 2026 World Cup: Spain tops both systems, but the official FIFA bracket shakes up the championship odds like never before.
Key Insights:
The agreement between FiveThirtyEight and KenPom on the top 5 provides strong confidence.
Bracket structure matters—Portugal benefits from favorable positioning while Germany faces a tougher path.
KenPom’s iterative approach showed slightly better predictive accuracy in the 2022 validation.
Predicted Champion: Spain (~10% probability)
Dark Horse: Argentina (KenPom’s pick)
Best Host Odds: United States (favorable Group D draw)
Group of Death: Group L (England, Croatia, Ghana, Panama)
Built for the Hex Virtual Hackathon 2026
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