Current Elo rankings
Win % vs next shows the probability of beating the team ranked directly below. Bands translate percentages into intuitive labels.
| # | Team | Elo | Win % vs next | Band | P | W | D | L |
|---|
Pairwise win probabilities
Read across: each cell shows the probability that the row team beats the column team on a neutral venue. Hover for detail.
Upcoming match predictions
Win probabilities based on current Elo ratings. Home advantage adds Elo points for home matches.
Historical Elo ratings
Year-end Elo snapshots from . Click a team in the legend to toggle visibility. Top 10 shown by default.
What is Elo?
Elo is a rating system originally designed for chess by Arpad Elo. It assigns each team a numerical rating that rises with wins and falls with losses. The size of the change depends on the opponent's strength: beating a highly-rated team earns more points than beating a weaker one. Crucially, Elo ratings produce win probabilities directly. If the gap between two teams is 100 points, the stronger team is expected to win roughly 64% of the time.
How this model works
This is a margin-of-victory-adjusted Elo system on the standard 1500/400 scale (the FiveThirtyEight/ELOR design). Each match updates ratings based on three factors: the result (win, loss, or draw), the margin of victory (larger margins move ratings more, with diminishing returns via a logarithmic dampener), and an autocorrelation adjustment (upsets move ratings more than expected results).
Additional model features include home advantage (applied at non-neutral venues), a Rugby World Cup match weight (RWC matches count double), cold-start seeding for teams entering the dataset after 1871, and a 10% regression to the mean between seasons.
Model parameters
| Parameter | Value | Meaning |
|---|
Data scope
Validation
Walk-forward prediction from January 2024: 76.8% hit rate on decisive matches (211 matches), Brier score 0.161 (lower is better). Spearman rank correlation of 0.959 against the official World Rugby rankings. Parameters (K=20, H=90, SR=0.10) were selected by grid search over 616 combinations, scored on mean Brier across three Rugby World Cup cycle windows (2015-2019, 2019-2023, 2023-2026).
Probability bands
Raw percentages are translated into six named bands, consistent with the football predictor:
| Band | Range | Meaning |
|---|---|---|
| Coin flip | 50 - 55% | Could go either way. Essentially even. |
| Too close | 55 - 60% | Slight lean but hard to call. |
| Tight | 60 - 65% | Meaningful edge, still competitive. |
| Slight edge | 65 - 70% | Clear advantage, upset still plausible. |
| Clear favourite | 70 - 85% | Strong advantage. Upset unlikely. |
| Strong favourite | 85 - 100% | Dominant. Result barely in doubt. |