01 · Discover
Find a market
Search markets with the discovery APIs. Get the slug, outcomes, and status — open or already resolved.
1-second Polymarket order books — free tier includes L2
Full bid/ask depth for Polymarket crypto markets, captured every second. Query books, prices, and liquidity through a REST API, Python SDK, or MCP server — not just midpoints.
1s captureL2 on free tierMCP serverBacktest AI
Research dataset
The Polymarket L2 dataset you can cite in a paper
897k order book snapshots at 1-second resolution, registered on Zenodo (10.5281/zenodo.22084114, August 2026) with a DataCite DOI and CC BY 4.0 licence. Free to download — valid in a data availability statement. Paid archives typically offer no persistent identifier.
- 897k L2 snapshots
- 805 resolved markets
- CC BY 4.0 licence
Published on
- ZenodoDOI 10.5281/zenodo.22084114
- Hugging FaceParquet mirror
- KaggleCSV download
- DataCitePersistent DOI
Side by side
Why 1-second L2 beats minute archives
Polymarket's API is great for live prices. Typical historical archives sample once per minute. We capture full bid/ask depth every second — built for crypto backtests and final-minute settlement research.
| Feature | Public API | Typical paid archives | PolyOrderbooks |
|---|---|---|---|
| Historical L2 order books | Current book only | 1-minute snapshots (typical) | 1-second full ladders |
| Free tier order books | No archive | Often none on free | Yes — Starter includes L2 |
| Finest query resolution | 1-minute prices | 1 minute | 1 second on every plan |
| AI / MCP access | Build your own wrapper | No official MCP | Official MCP server |
| Paid entry (L2 archive) | N/A | From ~$60/mo (typical) | Data from $19/mo (30-day window) |
Backtest AI
Backtest a Polymarket strategy in plain English
Describe a crypto up/down strategy in a sentence — “Buy DOWN on BTC 15m below 0.40, take profit at 0.55, stop loss at 0.30” — and Backtest AI turns it into executable rules and replays it over resolved Polymarket markets from the PolyOrderbooks archive.
- No strategy code — natural language becomes entry and exit rules.
- Fills walk the historical 1-second L2 book, so runs reflect partial fills, slippage, and exit reasons instead of an assumed mid price.
- A report plus an AI analysis — net P&L, win rate, profit factor, max drawdown, equity curve, and a plain-English read of what worked.
- Save backtests, export trades to CSV or the full report to JSON, and keep the conversation in your workspace.
118,251resolved crypto up/down markets
143.5ML2 order book snapshots
1scapture across the archive
How it works
Three steps. One API. Your client never talks to live Polymarket.
02 · Request a window
Pull prices and metrics
Choose a time range and resolution. Prices and liquidity use the same window so your charts and filters stay aligned.
03 · Replay depth
Walk the order book
Load historical bid/ask levels to estimate fills and slippage — detail a mid-price series cannot give you.
What we store
Indexed crypto markets with order books, prices, and metrics captured on the same 1-second timeline.
819.5kmarkets indexed
779.7Morder book snapshots
144.6Mprice snapshots
332.8Mmetrics snapshots
Full bid and ask ladders as [price, size] for each outcome.
Sample marketbitcoin-all-time-high-by-december-31-2026
2026-04-01T00:00:00ZMid0.052
Spread0.001
Resolution1s
Bids
Size0.0525,645
0.051425
0.0501,011
0.049644
Asks
Size0.0531,134
0.0581,085
0.0597,058
0.0601,428
/markets/bitcoin-all-time-high-by-december-31-2026/booksHow to connect
Query it, code it, or export it
Choose how you want to pull historical data — REST API, Python SDK, MCP for AI clients, or Enterprise S3 bulk export.
REST API
Markets, books, prices, and metrics over HTTPS — one API key, any language.
Python SDK
Official PyPI client (polyorderbooks) for scripts, notebooks, and backtests.
MCP server
1-second L2 order books in Cursor and Claude — official MCP server.
Enterprise S3 export
Sales-assisted bulk drops in Parquet, CSV, or JSON — one-time or on a schedule.
First time here? Read the API quickstart, then pick a path above.
Plans — 1s resolution on every tier
Free Starter includes order books. Upgrade for longer history and higher rate limits.
Starter
$0
Start free — no credit card required.
- Full Polymarket crypto market coverage
- Discovery, order books, prices, and metrics
- Finest resolution: 1s
- 60 requests/min · 1,000/day
- 3 days of history
- 1 free AI backtest
- 3 free strategy backtests
Build your plan
$19/mo
Pick a history window, then add speed and Backtest AI as needed.
History window
Speed
300 requests/min · 50,000/day
- Finest resolution: 1s
- 300 requests/min · 50,000/day
- 30 days of history
Get started
Pay by card or crypto
Backtest AI
$29/mo
Write your idea in plain English. We'll tell you if it's a money-maker.
- Strategy backtests — Unlimited
- AI backtests — 500 / month
- 8 crypto coins — BTC, ETH, SOL, XRP, HYPE, BNB, DOGE, ZEC
- 70k+ resolved markets to backtest
- AI-generated strategy analysis
- 30 days of market data for AI
- Data API access
Get started
Pay by card or crypto
Enterprise
Custom
Full data dumps, custom feeds, and bespoke delivery.
- S3 exports and dedicated support
- Custom rate limits, history, and granularity
- Private or dedicated access
- SLA and onboarding
Built for trading and research
Mid prices are easy to chart. Depth is what tells you whether a trade would have filled.
Simulate fills
Walk historical bid and ask levels when you size an order. Spot thin books and wide spreads before a backtest looks too clean.
Match signals to liquidity
Pull prices and metrics on the same window as the book. Focus on times the market was deep enough to trade.
Keep settled markets
After an event resolves, the market stays in our archive — including the winner — so you can still study it.
FAQ
Short answers before you open the docs. See all questions →
How is this different from the live Polymarket API?
The live API shows what is happening now. PolyOrderbooks stores history — past order books, prices, and liquidity — so you can replay a market after it has moved on.
How often do you capture data?
Open markets are snapshotted every second. Every plan, including the free Starter tier, can query down to 1s. Coarser buckets (1m–1d) are available on every plan.
Can I backtest Polymarket strategies with historical order books?
Yes. Use L2 bid and ask ladders to estimate fills and slippage instead of relying on mid prices alone. Pull prices and metrics on the same time window so signals and liquidity stay aligned.
Do I need a dashboard?
No. PolyOrderbooks is an API product. Use the dashboard for keys and usage; the full API reference is at docs.polyorderbooks.com — your integrations call the REST API directly.
Do you have a Python SDK?
Yes. The official polyorderbooks package is on PyPI (pip install polyorderbooks). Runnable examples live on GitHub. REST remains the core API; the SDK wraps the same endpoints.
Do you have an MCP server for Cursor or Claude?
Yes. @polyorderbooks/mcp-server on npm exposes historical order books, prices, and metrics as MCP tools in Cursor, Claude Desktop, and other MCP clients. Same 1-second archive as the REST API — install steps at polyorderbooks.com/polymarket-mcp-server.
How do I get access?
Create an account, verify your email, and generate an API key from the dashboard. Plan limits are enforced on the hosted API — see pricing and the docs to get started.
Is this affiliated with Polymarket?
No. PolyOrderbooks is an independent data product and is not affiliated with or endorsed by Polymarket.
Start with a free plan
Create an account, read the docs, and call the API. Upgrade when you need more.
Paid plans support card payments and 300+ cryptocurrencies.