Will the biggest earthquake on September 29, 2026 be 5.5 to 5.6?

This market resolves on the largest earthquake worldwide on September 29, 2026, and the 'No' side wins if the day's maximum magnitude falls outside the narrow 5.5–5.6 band. It is a single calendar day and a 0.1-wide interval, an extremely tight window for global seismicity.

USGS data show roughly 15–20 magnitude 4.5+ events per day worldwide and only about one event in the 5.5–6.0 range. Magnitudes follow the Gutenberg–Richter distribution, so the probability of landing specifically in 5.5–5.6 rather than 5.7 or 5.4 is small. Our model puts 'No' near 78%, because even if one strong event occurs that day, its magnitude will most likely sit outside this narrow corridor.

The market prices 'No' at just 1%, which looks clearly mispriced: the quote likely reflects thin liquidity or a stale automated price rather than actual statistics. For 'No' to win, the day's largest event simply needs to be below 5.5 or above 5.6, which is the dominant scenario.

The main risk is a rare coincidence: if the single largest event of the day is exactly 5.5 or 5.6, the position loses. Catalogue discrepancies (USGS versus EMSC) and post-hoc magnitude revisions could also push the final value into the disputed band.