
Prediction Markets
How prediction markets actually price an event
Contract prices are probabilities with a fee attached. Here is how to read them, and where the edge usually leaks away.
9 min read
21+ in most US states. Gambling and event trading involve risk of loss. Play responsibly.
Independent · United States · Data-led
Play Radar reviews regulated prediction markets, sportsbooks and online casinos using weekly price sampling and funded test accounts, not press releases.
Play Radar earns commission from some operators listed. It never influences our ratings or rankings. 21+ in most US states.

Sportsbooks
12 weeks of price sampling across major leagues
Ranked by our analysts
Rankings reflect our published methodology and are monitored continuously, last checked 27 August 2026. Offers shown are the best available to new customers in the selected market and are subject to the operator’s full terms.
Review methodology
We record odds and contract spreads every week across major leagues and event markets, then publish the averages rather than the headline promotion.
Every operator is tested on a funded account: deposit, verification, in-play behaviour and at least two withdrawals before we publish a score.
Bonus terms, settlement rules and stake limits are read from the operator’s own documents. Where marketing conflicts with terms, we quote the terms.
We check licence numbers against regulator registers and re-verify quarterly. Unlicensed operators are never listed.
Where we stand
A welcome offer is paid to you once. The margin inside a price, or the fee on an event contract, is charged every single time you place a wager or take a position. That is why our desk weights pricing and fees at 30% of every score and promotions at 10%, and why a book with a modest sign-up credit can still finish above one advertising a far bigger headline number.
We also refuse to blur product lines. Licensed real money casino play exists in eight states, online sportsbooks in most of the country, sweepstakes platforms under promotional law in most of the remainder, and event contract exchanges under federal commodities regulation. Those are four different legal frameworks with four different sets of consumer protections, so we score them separately and say plainly which one applies to you.
When we cannot verify something, we leave it out. No estimated payout times, no recycled operator marketing copy, and no legality claim that is not traceable to a statute, a regulator register or an operator disclosure.
Ranked on sampled margins and timed withdrawals.
How event contracts price real world outcomes.
Dual-currency play and the current state map.
Limits, self-exclusion and where to get help.

Prediction Markets
Contract prices are probabilities with a fee attached. Here is how to read them, and where the edge usually leaks away.
9 min read

Sportsbooks
Free bets are marketing. Margin is maths. A guide to calculating what a bookmaker really charges you.
7 min read

Casinos
Wagering multiples, game weighting, max win, max bet and expiry. Everything else is decoration.
8 min read

New Jersey Casinos
A direct NJ comparison of BetMGM, BetRivers, Caesars Palace, FanDuel, Borgata and PlayStar, including minimum deposits, offer mechanics and operator fit.
14 min read

US Prediction Markets
Polymarket US, Foregate, Underdog and Onyx compared on market structure, minimum funding, state availability and regulatory clarity.
12 min read
The questions readers send us most often about how this site is put together.