Underdog Exchange
Underdog Exchange is Underdog Fantasy's CFTC-regulated event-contract exchange. The reports include individual trade prints plus daily market volume and open interest.
About this page
Underdog volume is the daily_volume field from the public daily market reports, confirmed to equal the sum of that ticker's contracts_traded in the public trade-level reports — the same contracts convention used everywhere else on this site (not dollar volume). Categories are parsed from the sport code embedded in each ticker (e.g. UDXMLBGAMEWIN... → Baseball); bet type (Moneyline / Spread / Total) is parsed from the rest of that same ticker segment. Multi-leg parlays are reported as UDXCOMBO-<hash> tickers that carry no sport or bet-type code, so they are grouped as Parlays rather than split across sports.
The reports do not publish fees directly; the fee figures here are derived from Underdog's published schedule. Any Underdog fee on the Comparison page is derived from the exchange's published schedule — the same 0.07 coefficient Kalshi uses, but charged to both sides, so Underdog collects about twice per matched trade what Kalshi does. Contract sizes on this exchange can be fractional (unlike Kalshi's whole-contract trades), which is expected, not a parsing error.
Daily volume
Underdog contract volume from the public daily market reports. Gaps between bars are real — the exchange had no reported trades those days.
Single-game vs. parlay
Everything Underdog has reported so far is a sports contract, so the useful split is not sports vs. non-sports but single-game markets vs. multi-leg parlays.
Parlay volume and stakes
The same parlay band on its own, in contracts and in the money bettors put up for them.
Parlays are
Category mix
Volume by sport, parsed from each contract's ticker.
Bet type mix
Underdog Exchange lists moneyline, spread, total and matchwin contracts on the same games.
Top markets
Underdog Exchange's individual markets, ranked by volume.