Tater

The Window

The same event costs different money at every venue

Tater records prediction markets and sportsbooks side by side, continuously, and works out what a dollar of payout actually costs at each one — after the book’s margin, after the prediction market’s execution fee, after the exchange’s commission. The Window is that record, published openly, misses included.

663 markets live now (last good snapshot)26 days on the tapeToday: 17 fixtures recorded, 3 reads written

What a dollar costs today

Monday, August 10, 2026

Across 14 fixtures priced by 10 venues, the cheapest and dearest place to take the same outcome differed by an average of 3.4¢ per $1 of payout, and by as much as 11.8¢. On 6 of 28 outcomes the cheapest venue was a prediction market rather than a sportsbook. Here is the widest one:

Houston Astros at San Diego Padres

10 venues · quoted 1:29 AM UTC

To back San Diego Padres: cheapest at Kalshi for 44.7¢ per $1, dearest at Caesars for 56.5¢. Difference 11.8¢26.4% more of your own money for the same payout.

To back Houston Astros: cheapest at bet365 for 49.8¢ per $1, dearest at Kalshi for 59.7¢. Difference 10.0¢20.0% more of your own money for the same payout.

VenueBack San Diego PadresBack Houston Astros
Kalshimarket44.7¢+1.7 fee59.7¢+1.7 fee
Polymarketmarket45.2¢+1.2 fee58.2¢+1.2 fee
bet36554.5¢49.8¢
BetMGM48.8¢57.5¢
BetRivers51.0¢57.3¢
Bovada48.8¢57.5¢
Caesars56.5¢50.0¢
DraftKings45.9¢57.5¢
FanDuel47.6¢55.6¢
Pinnacle45.3¢59.5¢

What is on the board right now

419 of 663 live markets are not about sport at all — elections, rate decisions, company outcomes, chart positions. Anything with a market on it can be recorded, priced and written about the same way a match can.

Politics282
Economics41
Stock market16
Finance8
Tech10
AI3
Crypto3
Pop culture48

Venues: Kalshi 444 · Polymarket 200 · Smarkets 19

Most-traded non-sport market

Will NVIDIA be the largest company in the world by market cap on December 31?

70.5% on Polymarket · $999K volume · costs 71.5¢ per $1 of payout after fees

The views

Why this is unusual

01We price the cost of acting, not the headline number

Every venue charges in a different place. A sportsbook buries its margin inside the quoted odds. A prediction market takes an execution fee on a curve that peaks near 50c. An exchange takes commission on winnings, so its quote looks cheaper than it is. Comparing headline prices across those three is meaningless. We model all three and compare the only number that matters: what $1 of payout costs.

02It is a recording, not a screen

Most comparison tools query a price when you look. We keep a continuous cross-venue recording, roughly a month deep, so we can say which venue moved first, how far apart two venues were at a specific minute, and whether a move was a slow drift or a snap.

03It writes, and it shuts up

The recording produces written analysis without a human in the loop. Just as importantly, it produces nothing when there is nothing to say — the quiet days in the dispatch archive are real, not gaps.

04The record includes the misses

Settled events are scored against the closing price and published whether they flatter us or not. When a market closed at 10% and the thing happened, the market was wrong — we do not forecast, we chart. The scorecard names the biggest miss in the set.

05We are not a venue

We take no position and hold no book, so we are free to send you to a rival's better price. When a prediction market undercuts every sportsbook on an outcome, that is what the board says — and when it does not, the board says that too.

Archive

Every view has a dated permalink going back to when tracking began. The archive is the proof — including the days the engine had nothing to say.

The Window is the receipt. The feed is the product.

Everything above is generated from the same engine that runs the live board — the same cross-venue prices, the same fee models, the same routing. The feed is where you use it.

Open the live feed

Markets and prices shown are for informational purposes only. Nothing here is a recommendation or gambling advice. Always gamble responsibly. If you or someone you know has a gambling problem, call 1-800-GAMBLER or visit ncpgambling.org.