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1.00 to 0.99 ft 46.9%
Next is 3.00 to -1.01 ft at 34.6%. Only Polymarket lists this market, so there is no second price to compare.
Fair chance strips out each venue’s built-in margin (its prices add up to more than 100%), then blends the venues by how much has traded there, so the outcomes add up to 100%. Best Yes price is the cheapest ask across venues, and the payout is what a winning $100 stake returns before fees. Open a row for each venue’s contract name, bid and ask, and how closely their rules match.
Prices come from our regular polls of each venue, the oldest 3 min ago. Ages are as of when this page was built.
The top 3 outcomes on both venues, with the consensus between them. Hover for exact values.
Each venue’s resting orders for the selected outcome’s Yes contract, side by side. Top of book streams live; depth refreshes every 15 seconds.
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Enter a stake to see where it buys the most after fees, using each venue’s live order book.
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Buys at the asks resting now (taker orders), cheapest after fees first, from order-book snapshots up to 15 seconds old. Fees: Kalshi 0.07 × price × (1 − price) per share, rounded up to the cent; Polymarket 0.05 × price × (1 − price) per share (other / general rate). Fee calculator. Estimates only, not advice.
Live prediction market odds for "Lowest Mississippi level at St. Louis by November 30?". 1.00 to 0.99 ft leads at 46.9%. Next is 3.00 to -1.01 ft at 34.6%. $53K has traded across 5 outcomes on Polymarket. The market is expected to resolve by Dec 2, 2026.
This market will resolve according to the lowest gage height (river level), in feet, recorded at the Mississippi River at St. Louis, MO streamgage (USGS site 07010000) between market creation and November 30, 2026, as published by the United States Geological Survey (USGS) for parameter code 00065 under statistic code 30800. Exactly one outcome in this market will resolve to "Yes". The lowest daily reading in the window decides this market; the level does not need to be sustained. If USGS does not publish a reading for one or more days, this market will resolve according to the lowest reading among the days that are published. Values will be used exactly as published by USGS, without rounding. USGS reports gage height at this gage to 2 decimal places. Each range includes both of its stated bounds and consecutive ranges are contiguous, so every reading falls in exactly one range: a lowest reading of exactly -1.00 ft resolves the range beginning at -1.00 ft to "Yes" and every other range to "No". This market will resolve on the values published at the time of resolution, whether flagged provisional ("P") or approved ("A"); revisions published afterward will not be considered, except where the correction provision below applies. If any data remains unpublished or unfinalized, this market will remain open for up to 2 calendar days (ET) after November 30, 2026; it will then resolve based on the finalized data published up to that point. In case of obvious data integrity issues (i.e., erroneous data), the market may remain open until the end of the third calendar day (ET) after such data is first released to allow for corrections; this applies only to clerical or similar errors, not to USGS differing from other sources. If the source is unavailable, this market may be extended to December 15, 2026, 11:59 PM ET. If no data for the window is available by then, this market will resolve to "Below -3.00 ft". The primary resolution source for this market will be the USGS Daily Values service for site 07010000; however, a consensus of credible reporting may also be used. The service is available here: https://waterservices.usgs.gov/nwis/dv/?sites=07010000¶meterCd=00065&statCd=30800&startDT=2026-09-21&endDT=2026-11-30&format=rdb
It is the price of a Yes contract that pays $1 if the outcome happens. A 14¢ price means traders put the chance near 14%. Where two venues list the same outcome, we blend their last prices, weighting the venue with more trading volume more heavily (neither counts for less than a quarter). When only one outcome can win, each venue’s prices add up to a little over 100% (its margin); the fair chance removes that margin so the outcomes add up to exactly 100%.
A Yes contract pays $1 if it wins, so at the best ask a $100 stake buys 100 ÷ ask contracts. At 18¢ that is about 555 contracts, paying $556 (5.56x) if Yes happens. Venue fees and price slippage on larger orders are not included.
Each venue has its own traders, fees and order book. Contracts can also settle on slightly different terms, which is why each row lists how closely the rules match.
Only when you can buy Yes on one venue below what someone pays for Yes on the other, after fees, and both contracts settle the same way. We show the executable bid and ask so you can check.
Venue prices refresh every few minutes, and the order book and live quotes stream continuously. Each venue’s card shows when we last observed it.