Stream Kalshi and Polymarket prices and trades

Stream Kalshi and Polymarket trades, prices, quotes, books, volume, and resolutions through Solana Tracker Datastream.

Subscribe to pm:* rooms for prediction-market updates. Select an exchange, market, or event scope, and use the correct ID for that room. Price and orderbook subscriptions are market-specific.

Public Beta — Prediction market rooms use the same Datastream hub as other Solana Tracker streams.
Connect to wss://datastream.solanatracker.io/{apiKey} with your Data API key.

Connecting

const ws = new WebSocket("wss://datastream.solanatracker.io/YOUR_API_KEY");

ws.onopen = () => {
  ws.send(JSON.stringify({ type: "join", room: "pm:trades" }));
  ws.send(JSON.stringify({
    type: "join",
    room: "pm:market:polymarket:YOUR_TOKEN_ID:prices"
  }));
};

ws.onmessage = (event) => {
  const msg = JSON.parse(event.data);
  if (msg.type === "message") console.log(msg.room, msg.data);
};

Join / leave:

{ "type": "join", "room": "pm:trades" }
{ "type": "leave", "room": "pm:trades" }

Room types

Room	Purpose
pm:trades	Full trade tape (all exchanges)
pm:trades:significant	Trades with notional ≥ $25
pm:{exchange}:trades	e.g. pm:polymarket:trades
pm:market:{exchange}:{marketId}:trades	Single-market tape
pm:event:{exchange}:{eventId}:trades	All markets under one event
pm:market:{exchange}:{tokenId}:prices	Live top-of-book mid (+ displayPrice)
pm:market:{exchange}:{tokenId}:quotes	Streaming size-aware VWAP ladder
pm:market:{exchange}:{tokenId}:orderbook	Full book snapshots
pm:event:{exchange}:{eventId}:volume	Live cumulative USD volume for an event
pm:market:{exchange}:{tokenId}:volume	Live cumulative USD volume for one outcome
pm:crypto:{asset}	Chainlink underlying (BTC/ETH/…) — not outcome chance
pm:market_lifecycle / pm:resolution	Lifecycle and resolution fan-out

Price, quote, and orderbook subscriptions require a market ID. There is no global pm:prices room.

notionalUsd is price × quantity (USD). The significant room uses threshold $25.

Event rooms accept identities included in the payload, such as eventId, eventSlug, gammaEventId, or a Kalshi eventTicker.

Volume example

Crypto 5m windows — join with the event slug:

{ "type": "join", "room": "pm:event:polymarket:btc-updown-5m-1785347100:volume" }

{
  "type": "message",
  "room": "pm:event:polymarket:btc-updown-5m-1785347100:volume",
  "data": {
    "type": "volume",
    "channel": "volume",
    "exchange": "polymarket",
    "marketId": "{tokenId}",
    "timestamp": 1785347120123,
    "eventId": "btc-updown-5m-1785347100",
    "volume": 48210.55,
    "marketVolume": 24105.27,
    "delta": 42.5
  }
}

Replace the displayed volume with the latest frame. Fields include volume, marketVolume, delta, and eventId.

Quotes vs REST

Join pm:market:polymarket:{tokenId}:quotes for a streaming size-aware VWAP ladder. For arbitrary sizes use REST GET /v1/markets/{id}/quote on prediction-market-api.solanatracker.io.

Prices vs crypto underlying

Feed	Room	Meaning
Outcome chance	pm:market:polymarket:{tokenId}:prices	CLOB top-of-book mid
Underlying	pm:crypto:{asset} / pm:crypto:{asset}:prices	Chainlink USD ticks

IDs

• Room segments are lowercase.
• Polymarket market rooms require decimal CLOB token IDs (not 0x condition ids).
• Kalshi tickers appear uppercase in many REST payloads but lowercase in room names.

API reference

In the Datastream nav, Prediction Market rooms are grouped as:

Group	Rooms
Prediction Markets — Trades	pm:trades, significant, exchange / market / event trades
Prediction Markets — Prices	market prices, quotes, orderbook
Prediction Markets — Volume	event and market volume
Prediction Markets — Lifecycle	lifecycle and resolution
Prediction Markets — Crypto	pm:crypto:{asset}
Prediction Markets — Feeds	exchange, market, event, type, category, series, status, sport