Historical Polymarket order book API — query archived L2 bid/ask depth, outcome prices, and liquidity metrics for crypto prediction markets.

Independent data product. Not affiliated with or endorsed by Polymarket.

PolyOrderbooks stores historical Polymarket market data so you can replay past order books — not just live snapshots or mid prices.

• L2 order books — bid/ask ladders as [price, size] per outcome
• Prices & metrics — outcome prices, volume, liquidity, spread on the same time window
• Discovery — search series, events, and markets (crypto coverage today)
• Resolved markets — settled markets stay queryable, including the winner
• Read-local API — your client calls our archive; read paths do not hit live Polymarket

Open markets are captured every second. Starter plans query down to 60s resolution; Pro and Scale unlock 1s.

export POLYORDERBOOKS_API_KEY="pob_your_key_here"

curl -s -H "X-API-Key: $POLYORDERBOOKS_API_KEY" \
  "https://api.polyorderbooks.com/v1/markets?search=bitcoin&limit=5"

Create a free API key: polyorderbooks.com/signup

• Email: contact@polyorderbooks.com
• X: @polyorderbooks