Can ChatGPT, Gemini and Claude predict sports results?
Short answer
Not much better than a simple rule. Since 2026-07-27, ChatGPT, Gemini and Claude have predicted the final score of 1,209 completed MLB, WNBA and European football games before kickoff, using the same ESPN data and the same prompt, with no betting odds. Their consensus picked the winner in 56.5% of games (95% CI 53.7%–59.3%), while always picking the home team scored 53.0% on the same games. The best single model so far is Claude at 57.0%.
Accuracy by model
| Model | Games | Winner accuracy | 95% CI | Mean score error |
|---|---|---|---|---|
| ChatGPT (OpenAI Codex CLI) | 1,155 | 55.9% | 53.1%–58.8% | 5.88 |
| Gemini (Google) | 1,176 | 54.6% | 51.7%–57.4% | 6.05 |
| Claude (Anthropic) | 1,159 | 57.0% | 54.2%–59.9% | 5.91 |
Accuracy by league vs. always picking the home team
| League | Games | AI consensus | Home team | Difference (pp) |
|---|---|---|---|---|
| MLB | 862 | 56.5% | 54.1% | +2.4 |
| WNBA | 136 | 73.5% | 58.8% | +14.7 |
| Premier League | 40 | 42.5% | 27.5% | +15.0 |
| La Liga | 53 | 45.3% | 47.2% | -1.9 |
| Bundesliga | 35 | 51.4% | 51.4% | +0.0 |
| Ligue 1 | 36 | 30.6% | 44.4% | -13.9 |
| Serie A | 40 | 52.5% | 47.5% | +5.0 |
| Champions League | 7 | 71.4% | 85.7% | -14.3 |
Football (soccer) has draws, so its home-team baseline counts only home wins and is not comparable with baseball or basketball.
Method
Every evening (Taiwan time) the pipeline pulls each next-day game from ESPN: last six head-to-head results, each team's last five games, injury lists, venue and weather, and for baseball the probable starting pitchers. The same text is sent to the three models' official command-line tools. Each model returns a final score and a confidence value. Predictions are written once before the game starts and never edited; final scores are added after the game, misses included. Betting odds are deliberately excluded so the models judge on their own instead of copying the market. Daily prediction sets are hash-chained for tamper evidence.
Data and citation
Full game-level data: predictions.csv · predictions.json, licensed CC BY 4.0. Suggested citation: AI Sports Info (aisportsinfo.com), “ChatGPT / Gemini / Claude sports score prediction ledger”, CC BY 4.0. Contact: aisportsinfo.com@gmail.com. This site publishes predictions and results only and gives no betting advice.