Platform comparison
| Platform | YES odds | NO odds | Fee | KYC | Settlement | |
|---|---|---|---|---|---|---|
Polymarket (via BTC Prediction) Pick polygram.ink (preferred broker) |
42% | 58% | 0% (USDC on-chain) | No-KYC up to $1,500 | USDC, auto via UMA oracle | Open live market → |
Polymarket (direct) polymarket.com |
42% | 58% | 0% | Geo-blocked in US/UK/EU | USDC, on-chain | Open live market → |
Kalshi kalshi.com |
— | — | Up to 7% per trade | US-only, KYC required | USD | Open live market → |
Betfair Exchange betfair.com |
— | — | 2-5% commission | Full KYC from first trade | GBP / EUR | Open live market → |
Manifold Markets manifold.markets |
— | — | Play-money (mana) | None — play-money | Mana (no cash-out) | Open live market → |
Outcome probabilities
Current market-implied probability for each outcome, from the live order book.
| Outcome | Probability |
|---|---|
| 26°C | 42% |
| 25°C | 36% |
| 27°C | 12% |
| 28°C | 5% |
| 21°C or below | 0% |
| 22°C | 0% |
| 23°C | 0% |
| 24°C | 0% |
| 29°C | 0% |
| 30°C | 0% |
| 31°C or higher | 0% |
Market context
Seoul's peak temperature on 18 July 2026 will be measured at Incheon International Airport Station and resolved against historical weather records via Wunderground. July represents the height of South Korea's summer monsoon season, with typical daily highs ranging between 28–32°C, though extreme heat events have pushed readings above 35°C in recent years. The settlement mechanism uses USDC on-chain, with resolution tied to a single authoritative data point captured across all recorded times on that calendar date.
Historical precedent shows Seoul's July temperatures have grown more volatile over the past decade. The 2018 heat wave saw Incheon record 36.1°C on 24 July, whilst more moderate summers have peaked around 29–30°C. The 0% crowd probability suggests traders are either awaiting clearer seasonal forecasts or treating this as a placeholder until nearer the date. Comparable weather markets on btc-prediction.bet typically see meaningful probability shifts 10–14 days before settlement as meteorological models converge and atmospheric conditions stabilise.
Traders should monitor the Korea Meteorological Administration's extended forecasts from mid-July, particularly tracking upper-level ridge positioning and tropical cyclone activity in the Western Pacific. Funding rates on perpetual weather derivatives occasionally spike ahead of major seasonal inflection points, though direct correlation to spot temperature outcomes remains weak. The settlement window closes at 12:00 UTC on 18 July, meaning final readings must be confirmed before Asian market hours conclude.
Methodology
Methodologically this overview focuses on on-chain pricing: Polymarket's live mid comes from the Polygon conditional-token order book and settles automatically in USDC. The other three venues — Kalshi, Betfair, Manifold — sit alongside as off-chain reference points so you can see how the contract translates across regulatory and settlement regimes.
Resolution & payout
Settlement is on-chain via UMA Optimistic Oracle. A proposer posts the outcome with a bond, a two-hour dispute window opens, then the smart contract lifts winning conditional tokens to 1 USDC and sends payments to holders' wallets automatically. No withdrawal fees beyond Polygon gas.
Off-chain venues (Kalshi, Betfair, Smarkets) settle in local fiat through bank-side clearing — faster than SWIFT, slower than on-chain. Manifold pays no real cash.
FAQ
- What are crypto prediction markets?
- Crypto prediction markets are on-chain smart contracts where you buy YES or NO shares on a future crypto event (e.g. "BTC above $100k by year-end"). The market price between 0¢ and 100¢ is the implied probability.
- What does a transaction cost on Polygon?
- Polygon gas is typically under $0.01 per transaction. A full trade cycle (Approve + Order + Fill) totals around $0.03 — compared to $5-50 on Ethereum mainnet.
- Can I use Bitcoin directly?
- No, Polymarket operates exclusively in USDC on Polygon. You can bridge BTC to USDC via an exchange or bridge service and deposit on Polygon — typically 10-30 minutes processing time.
- How does UMA secure the resolution?
- The UMA Optimistic Oracle uses a bond system: a proposer posts a bond, a two-hour challenge window opens. On dispute the losing side forfeits the bond — financial incentive for honest resolution.
- Which crypto markets exist on Polymarket?
- Currently active markets include BTC/ETH/SOL price targets, halving dates, ETF approvals, hard-fork outcomes and Layer-2 TVL thresholds. The list updates weekly; biggest volume sits on BTC and ETH price forecasts.
Trade Highest temperature in Seoul on July 18? on BTC Prediction
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