How settlement works

How a call locks

• A call is timestamped the moment it is placed. Its open price is the latest Binance-fed market snapshot at that moment, stored on the call as the reference open price. No live price, no call.
• The crowd split (share of the last 24h calling UP) is stamped onto the call at open — it can’t be recomputed later to flatter anyone.
• One open call per account at a time, and a placed call can’t be edited or deleted. A wrong call stays on the record.

How it settles

Horizons are 1h, 24h, 7d, and 30d; expiry is the open timestamp plus the horizon. At settle time we fetch the Binance 1-minute candle covering the exact expiry minute and settle on its close — not on whatever price happened to be cached when the settlement job ran. That candle is persisted to our database as evidence, and the receipt records the provenance: settle_price_source = candle_1m with the candle’s minute as settle_price_at.

If Binance can’t return that exact minute (outage, delisting — a neighboring candle doesn’t count), we don’t substitute a candle from the wrong minute. The call settles on the latest market snapshot at the settlement tick instead, and the receipt says so: settle_price_source = snapshot. The fallback is disclosed on the receipt and in the digest entries below, never dressed up as a candle.

• UP wins when close > open; DOWN wins when close < open. An exact tie loses, whichever way you called it — no rounding grace.
• Result % = (close − open) ÷ open × 100, computed from the stored open and settle prices.
• Settled history is public immediately — never delayed, never paywalled.

Check us

Every completed UTC day gets one digest row. The day’s settled calls — ordered by settle time, then id — are serialized to canonical JSON and hashed (SHA-256) into an entriesHash. That hash is then chained: chainHash = sha256(previous chainHash + entriesHash), with the first day chaining from an empty string. Days with zero settles still get a row, so a missing day can’t be passed off as a quiet one. Editing or deleting any historical settle changes that day’s entries hash and breaks every chain hash after it.

GET https://app.bitpredict.io/api/public/settlement-digest
GET https://app.bitpredict.io/api/public/settlement-digest/<YYYY-MM-DD>

To verify a day yourself:

1. Fetch the day. The response contains the stored digest row and the full canonical entries array it hashed.
2. Compute sha256(JSON.stringify(entries)) — it must equal entriesHash.
3. Compute sha256((prevChainHash ?? "") + entriesHash) — it must equal chainHash.

The endpoint also recomputes both hashes from today’s live rows on every request and returns a consistent flag — a verification we could quietly skip wouldn’t be a verification. Both endpoints are unauthenticated and CORS-open. Only completed UTC days are digested; today is still in progress.