Grade C · 61%RelatedOutcome mapping: same
Kalshi vs Polymarket: Will the US confirm that aliens exist by September 30
Two contracts on the same event, priced by two separate crowds. Where they disagree, one of them is wrong — or the contracts are not quite the same question.
Kalshi 1.0% vs Polymarket 0.3% on Will the US confirm that aliens exist by September 30 — a 0.8 point prediction-market gap.
Live comparison
Kalshi
1.0%
—Polymarket
0.3%
—- Disagreement
- 0.8 pts
- Match confidence
- 61%
- Theoretical edge
- none
Side by side
Probability history
Both venues on one axis, with the gap beneath
KalshiPolymarket
No history available for this range yet.
How confident is this match?
Deterministic scoring first; the model may only downgrade
- Title
- 51%
- Entities
- 0%
- Dates
- 100%
- Threshold
- 100%
- Polarity
- 100%
- Rules
- 71%
Deterministic score 61%. Not yet semantically verified.
These contracts have not been semantically verified yet, so no rule-by-rule comparison is available. The grade rests on deterministic scoring alone.
Theoretical cross-market edge
Grade A pairs only, from executable book prices with depth simulation
Theoretical edge is calculated only for Grade A pairs, where the two contracts appear materially equivalent for settlement analysis. This pair is graded C, so the venues are compared for probability and sentiment only.
Why are these diverging?
Explanation pending
An evidence-grounded explanation is written once this market gathers enough confirmed price and trade evidence. Every number on this page is already live.
Event timeline
No timeline events yet
Timeline entries appear once price or trade activity crosses a reporting threshold.
Notable trades on both venues
Past 24 hours, ranked by notional
No sizeable trades recorded
Neither venue has printed a trade above the reporting threshold on this event in the last 24 hours.