How the numbers work
What is "best-price share"?
Every scan, The Odds Gap checks every book for every side of every game (home win, away win). A book's best-price share is the percentage of those scans where it offered the single highest payout. Higher means the book leads the market more often.
What is "matched lines"?
The "Market Breadth" view credits a book for beating whoever else happened to quote a game — so a wide-coverage book gets credit on games a sharp book never posted. It measures how often a book leads across the whole market we track, partial-coverage games included. The "Matched lines" view is the like-for-like counterpart: pick a set of books, and it only counts games where all of them quoted the same market at the same line, then ranks who had the best price within that set. Smaller sample, but a fair, replicable head-to-head. Add Pinnacle or Kalshi to see how the sharp books rank once coverage is equalized.
How often does the site scan?
Every hour from 7 AM to 9 PM ET (15 scans/day) across every in-season league we track — NBA, WNBA, MLB, NHL, NFL, college football and basketball, soccer (including the World Cup), and UFC. Each scan hits every tracked sportsbook plus the prediction markets (Kalshi, Polymarket, ProphetX) simultaneously. Data accumulates from every scan for the trend lines.
Why no "today" view?
The page only shows completed ET days. Today's grades aren't displayed because they'd reflect partial-day data that hasn't covered the full slate of scheduled games yet. "Yesterday" is the most recent fully-completed day.
Polymarket on shorter windows
Polymarket only appears in 7-Day once it has 7 ET days of recorded history, and in 30-Day once it has 30. Until then it's hidden from those windows so the percentages aren't computed on a partial denominator. Yesterday and All-Time always include Polymarket once it has any data.
Why is Kalshi different?
Kalshi is a regulated prediction-market exchange, not a traditional sportsbook. Its no-juice structure produces lower implied prices than sportsbooks by design, so it tends to lead the market on best-price share. Treat its number as a structural difference rather than a head-to-head sportsbook comparison.
What this page is not
It's not a recommendation. Best-price share is one factor among many — app reliability, withdrawal speed, promo offers, and availability in your state may matter more on any given bet. Use this as one input into your own decision.