Highest temperature in Beijing on July 23?

Platform comparison

Market context

Beijing’s peak temperature will be set by the highest reading at Beijing Capital International Airport on 23 July, with the market resolving from Wunderground’s daily history page for ZBAA. In practical terms, the key question is whether the day tops out in the high 20s or edges into the low 30s Celsius, because that is where July climatology in Beijing most often sits.[2]

The current crowd-implied 0% YES reading on the platform should be treated as a pricing artefact rather than a weather view, since this market is settled into temperature bands and can move sharply as forecast runs change the expected timing of rain or cloud cover. Polymarket displays outcomes as implied probabilities, whereas Kalshi-style books more often present a contract price in dollars and Smarkets/Betfair-style exchanges translate the market through decimal odds; on a direct comparison, the same weather view can look very different once fees, spread, and liquidity are applied. This matters here because a 28°C or 29°C outcome can still dominate even if broader probability screens look near-zero in a thin book.[1][2]

For traders, the main catalysts are the daytime forecast cycle, any changes in convection or thunderstorm timing, and whether the airport station reports a late-afternoon maximum before the settlement cut-off. Because the market settles on the airport’s observed high rather than a citywide average, local cloud breaks, storm outflows, and runway-area conditions can matter more than general Beijing forecasts. KYC access and fee structure also differ across venues: Polymarket and Kalshi typically require tighter onboarding than open exchanges, while Betfair and Smarkets prices can be shaped further by commission and cross-matching, which affects how cleanly a weather view is expressed.

Sources: 1 · 2

Methodology

This page compares Highest temperature in Beijing on July 23? specifically across Polymarket, Kalshi, Betfair Exchange and Smarkets. The live probability is the Polymarket mid; the comparison columns summarise each venue's fee structure, KYC, settlement currency and payment rails. Every CTA routes to Kalshi Alternative UK, 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

Polymarket vs Kalshi — which is better?

Depends on your location. Kalshi is CFTC-regulated, US-only with full KYC. Polymarket is global, on-chain, no KYC up to $1,500. Polymarket has ~10x higher liquidity but higher regulatory risk.

Which platform has the deepest liquidity?

Polymarket — by a wide margin. Top markets reach $50-500M volume, Kalshi ~$200M cumulative, Betfair similar. Deeper liquidity means your trade moves the quote less.

Is Betfair a Polymarket alternative?

Only partially. Betfair Exchange is UK-focused with a sports-betting emphasis; they have politics markets but with thinner liquidity than Polymarket. Settlement in GBP/EUR, 2-5% commission on winnings.

Are all these platforms regulated?

No. Kalshi is CFTC-regulated (US). Betfair and Smarkets are UK Gambling Commission licensed. Polymarket operates without explicit regulation — a different risk profile than a regulated sportsbook.

Which platform supports Klarna/SOFORT?

Directly: none. Polymarket accepts only USDC on Polygon. Kalshi Alternative UK offers a fiat on-ramp via Klarna or SOFORT (DE/AT/CH) and converts internally to USDC for the Polymarket order book. T+1 processing.