Polymarket Calibration

How often do markets at X% probability actually resolve YES?

Polymarket is highly accurate

When Polymarket shows 70%, events actually happen about 70% of the time. This calibration shows that prediction markets are reliable probability forecasters.

Calibration Curve

Comparing predicted probabilities (X-axis) to actual outcomes (Y-axis). Perfect calibration = diagonal line.

Perfect Calibration

Polymarket Actual

Accuracy by Timeframe

How accurate are Polymarket probabilities at different times before resolution?

1 month before resolution90.5% accurate

1 week before resolution89.2% accurate

1 day before resolution88.6% accurate

4 hours before resolution94.2% accurate

Note: "Accurate" means markets above 50% resolved YES, and markets below 50% resolved NO. Data via Dune Analytics.

Understanding Market Bias

Slight Overconfidence

Polymarket tends to slightly overestimate probabilities. For example, events at 80% actually happen about 78% of the time. This is common across prediction markets due to acquiescence bias and herd mentality.

Higher Volume = More Accurate

Markets with high trading volume tend to be more calibrated. More traders mean more diverse perspectives and better price discovery.

Actionable for Traders

Understanding this slight overconfidence can inform betting strategies. Markets showing 85%+ might be slightly overpriced, presenting opportunities for contrarian bets.

Why Prediction Markets Beat Polls

Prediction Markets ✓

•Real money creates accountability
•Continuously updated with new info
•Aggregates diverse perspectives
•Self-correcting through arbitrage

Traditional Polls

•No cost to being wrong
•Snapshot at one moment in time
•Sample may not be representative
•Subject to response bias

Calibration data sourced from Dune Analytics and historical Polymarket resolution data. Updated monthly.