Polymarket Endpoints
Polymarket Orderbook History API
Orderbook returns the live bid/ask ladder for a Polymarket market token, proxied from clob.polymarket.com.
Get Polymarket orderbook
Current orderbook depth (bids and asks) for a Polymarket market, proxied live from clob.polymarket.com.
Live GET Request
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Live Response
Click Try It to run this GET request against the API.Request
curl 'https://api.thepredictionmarkets.com/api/v2/polymarket/orderbook-history?market_slug=2026-nba-champion' \
-H 'X-API-Key: YOUR_TPM_API_KEY'Response
{
"bids": [
{ "price": "0.49", "size": "2500" },
{ "price": "0.48", "size": "1200" }
],
"asks": [
{ "price": "0.50", "size": "3100" },
{ "price": "0.51", "size": "900" }
],
"market_slug": "2026-nba-champion",
"token_id": "0xabc123..."
}Query Parameters
| Name | Type | Required | Default | Example | Description |
|---|---|---|---|---|---|
| market_slug | string | No | - | 2026-nba-champion | Polymarket market or event slug. Used to look up the CLOB token ID. |
| token_id | string | No | - | 0xabc123... | Polymarket CLOB token ID. Overrides market_slug when provided. |
| outcome_index | integer | No | 0 | 0 | 0 for first/YES token, 1 for second/NO token. |
Response Fields
| Field | Type | Example | Description |
|---|---|---|---|
| bids | object[] | - | Bid levels sorted descending by price. Each has price and size. |
| asks | object[] | - | Ask levels sorted ascending by price. Each has price and size. |
| token_id | string | - | CLOB token ID used for this orderbook lookup. |
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