Arizona Diamondbacks vs. San Francisco Giants

Platform comparison

Active sub-markets

Market context

The Arizona Diamondbacks travel to San Francisco to face the Giants on 25 May at 22:05 UTC, with the market settlement window extending to 1 June. The 87% implied probability favouring Arizona reflects their stronger 2024 regular-season record and recent performance metrics. Across major platforms, this probability translates differently: Polymarket displays it as a decimal of approximately 1.15 for Arizona, whilst Kalshi and Betfair express the same odds in their native formats (around 7/20 and 0.87 respectively). Fee structures diverge meaningfully—Polymarket charges 2% on winnings, Kalshi applies variable fees depending on order type, and Betfair's commission sits at 5% on net profit. KYC requirements also vary, with Kalshi enforcing stricter US-resident verification than Polymarket's broader international access, affecting liquidity pools for this matchup.

Historical context suggests that regular-season head-to-head records between division rivals carry predictive weight, though home-field advantage at Oracle Park has historically compressed win probabilities. The Giants' bullpen depth and Arizona's offensive consistency form the technical foundation for the current odds. Traders should monitor roster announcements through late May, particularly regarding starting pitcher assignments and any injury updates to key position players. Recent weather forecasts for San Francisco Bay Area conditions on game day may influence scoring expectations, whilst any schedule changes or postponements would trigger the market's contingency clause, keeping it open until completion rather than resolving prematurely.

Methodology

This page compares Arizona Diamondbacks vs. San Francisco Giants specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. Live odds come from the Polymarket order book; the other venues' contract details are maintained manually because their APIs aren't directly comparable. Every CTA routes to PolyGram, which mirrors the Polymarket order book at 0% fees.

Resolution & payout

Polymarket settles via UMA Optimistic Oracle on Polygon. A proposer posts the outcome with a bond, the two-hour window runs, then the smart contract pays USDC.

Kalshi settles USD through the CFTC-regulated clearinghouse — the cleanest variant, with heavier KYC. Betfair Exchange settles in account currency (GBP/EUR), net of 2-5% commission. Smarkets follows the same model as Betfair with a lower default 2% commission.

FAQ

Where can I trade this market with the lowest fees?

On PolyGram, which mirrors the Polymarket order book at 0% fees. Kalshi charges up to 7% per trade; Betfair Exchange takes 2-5% commission on net winnings.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

What does it cost to trade on PolyGram?

Zero. PolyGram routes every order to the live Polymarket order book; the only cost is the Polygon network fee, typically under $0.01 per transaction.

Do I need to KYC for this market?

Not under $1,500 of lifetime trading volume. Above that threshold, PolyGram triggers a quick verification flow that finishes in minutes.

How reliable are the quoted odds?

The YES/NO percentages are the live mid-prices of the Polymarket order book. On deep markets they move every few seconds; on thinner ones you'll see short plateaus.