The Automated Polymarket Trading Bot
Place GTC/GTD/FOK orders on Polymarket's CLOB automatically. Arb cross-venue, value bet with sharp references, execute in ~25ms.
Why this Polymarket bot beats the alternatives
Search for a Polymarket trading bot and you'll find two things. On one side: GitHub repos built around py-clob-client with example scripts that post a single order. On the other side: analytics dashboards and copy-trading tools that show you what whales are doing but don't actually place orders. Claw Arbs sits in the third category, which is where the money is: a real execution engine that watches the CLOB, calculates net edge (gas included), and fires automatically.
| Feature | Claw Arbs | DIY Python / py-clob-client | Polymarket Analytics / copy tools |
|---|---|---|---|
| Auto-execution | Yes | Manual code | No (analytics only) |
| CLOB WebSocket ~25ms | Built in | Self-implement | N/A |
| Gas-cost-aware edge math | Baked into every calc | Must code | None |
| Cross-venue arb (Kalshi, sportsbooks) | Yes | No | No |
| Paper trading | Yes | DIY | N/A |
| GTC/GTD/FOK/FAK order types | All supported | Manual | N/A |
| Naked leg tracking | Yes | Manual | N/A |
| Price | Free | Free | $29-$99/mo |
DIY is fine if you want a side project. You can build a working Polymarket bot with py-clob-client in a weekend. What takes months is the execution layer around it: reliable WebSocket reconnection, gas-aware edge calculation that doesn't fire on dust trades, order type selection based on liquidity, and the risk pipeline that prevents you from leaving a leg naked when the hedge venue's WebSocket stalls. Analytics tools are even further from tradeable: they show you trends, not actionable edges, and when they do surface something, the trade window has already closed.
Claw Arbs collapses the whole stack into one async Python process. Polymarket's CLOB WebSocket sits next to Kalshi's and the sharp sportsbook feeds in the same price cache. When any feed updates, the relevant arb engine recomputes in sub-millisecond time and fires if the edge clears your threshold. For Polymarket-only strategies (like intra-market bracket arbs), the bot uses the same pipeline. For cross-venue (Polymarket vs Kalshi, Polymarket vs Pinnacle), both legs get fired with coordinated order types to minimize the window where you're naked. Use our prediction market EV calculator to model edges before you trust the bot with real USDC.
How it works in 3 steps
Connect your Polygon wallet
Fund a Polygon wallet with USDC.e for trading and a small amount of MATIC for gas. Drop your private key into the local secrets directory (most users create a dedicated hot wallet for the bot). Claw Arbs reads it once at startup, signs CLOB orders locally, and never sends the key anywhere. No custodian, no bridging service, no third-party proxy.
Choose a strategy
Pick cross-venue arbitrage (lock in an edge between Polymarket and Kalshi or a sharp sportsbook), sharp-vs-Poly value betting (take directional shots when Polymarket drifts from the sharp fair), or both. Each strategy has independent thresholds: minimum edge (after gas), maximum edge (to filter obvious data errors), minimum orderbook depth, per-market cooldowns.
Paper trade, then go live
Set paper_trading=True to run the full pipeline without submitting CLOB orders. You'll see simulated fills based on real orderbook depth and edge-log events exactly as they'd appear live. When the paper P&L behaves, flip live_execution=True. A week of paper is the usual baseline before going live with real USDC.
What markets it covers
Polymarket's market universe is broader than Kalshi's on politics and crypto-native events, and narrower on sports. The bot subscribes to token IDs for whatever you enable, and the scan cycle rebuilds the pair registry every ~30 seconds. Out of the box, you get coverage across:
- Sports: EPL, UEFA, NFL spreads, moneylines, totals
- Politics: US elections, Eurozone elections, nominations
- Crypto-adjacent events: token price milestones, protocol outcomes
- Macro: Fed rate decisions, inflation prints, GDP
- Entertainment & cultural events: awards, releases, pop culture odds
For cross-venue arbitrage, the matcher pairs Polymarket tokens with Kalshi tickers automatically using game keys and market types. For pairs that don't exist on Kalshi (most crypto and political nominations), you still get intra-market arb: the bot watches multi-outcome markets where the sum of Yes probabilities sometimes drifts past 1.00 across outcomes, creating a lock-in opportunity. See the Polymarket arbitrage bot deep dive for how this works in detail.
Prediction market + sportsbook = killer combo
Polymarket alone is a great venue. It's deep on politics, has native crypto audiences that don't overlap with traditional sportsbook users, and prices markets that sportsbooks don't touch (cabinet nominations, AI milestones, cultural events). But single-venue bots on Polymarket are limited by the fact that Polymarket's users are the ones setting prices. Retail flow creates drift, but without a reference, you don't know which side of that drift is wrong.
The fix is to anchor Polymarket prices to sharp external sources. For sports markets, that's Pinnacle/PS3838 decimal lines (the sharpest odds in the world on major games). Devig them to get a fair probability, compare to Polymarket's token price, and take the value side when the gap exceeds your threshold. For politics and macro, it's Kalshi: two prediction markets with different user bases frequently disagree by enough to lock in a cross-venue arb. Claw Arbs does all of this automatically. The prediction markets hub and the guide on Polymarket value betting explain the mechanics. The cross-venue arb flow is covered in the Polymarket arbitrage bot writeup.
The other reason Polymarket belongs in a serious trading stack: it doesn't limit winners. Traditional sportsbooks (Bet365, FanDuel, DraftKings, William Hill) cap, ban, or close accounts that consistently beat the line. Polymarket is a crypto-native exchange. Every trade has a counterparty, the protocol doesn't care who wins, and your wallet doesn't get flagged for making money. For anyone building a long-term automated trading practice, this structural fact matters more than any specific fill. Prediction markets let you compound.
Gas awareness
Polygon gas is cheap compared to Ethereum mainnet, but it's not zero. At current rates, a single CLOB order transaction costs roughly $0.05 to $0.15 depending on network congestion. On a $1,000 trade that's a rounding error. On a $20 trade it's 0.25% to 0.75% of your stake, which can turn a 1% edge into a break-even or losing trade. A Polymarket bot that ignores gas will blow up slowly on small edges.
Claw Arbs subtracts gas from every edge calculation before the decision to fire goes through. The gas buffer is configurable: you can set it conservatively (assume worst-case congestion) or track recent average gas to stay tight. The bot also enforces a minimum stake recommendation so each trade amortizes gas properly. If the edge isn't big enough to clear gas plus your safety margin, the opportunity gets dropped and logged to the edge log. You see exactly why each trade was skipped, which is essential for tuning thresholds.
Safety & risk controls
Polymarket is permissionless, which is the good news and the bad news. Good: you can trade without KYC beyond what your wallet has done on-chain. Bad: nothing stops a misconfigured bot from draining your USDC. Claw Arbs runs every trade attempt through a layered pipeline:
- Kill switch: a single toggle that halts all new orders instantly. First thing to hit when something looks off.
- Naked leg tracking: if leg A fills on Polymarket but leg B on Kalshi or a sportsbook fails, the match is flagged. Both arb engines halt new trades on that match until it's resolved.
- Cooldowns per market: after a fill (or a near-miss), the market enters a cooldown window to avoid firing on the same stale price twice.
- Exposure limits by venue and total: cap how much USDC can sit on Polymarket, how much on each sportsbook, and across everything combined.
- Per-match rate limiting: stops the bot from trading the same match 20 times in a row during a fast-moving window.
- Deduplication of opportunities: the same arb can trigger from multiple price updates; dedup ensures only one order goes out.
- Paper trading mode: run the whole pipeline against live data without sending orders. Required reading before going live.
Together these 14 checks run on every trade attempt. If any step fails, the opportunity is dropped and logged. The edge log captures every decision, which is how you tune thresholds over time. The Claw Arbs homepage has the full architecture diagram and live-run screenshots.
FAQ
How does the bot connect to Polymarket's CLOB? +
The bot opens a WebSocket connection to Polymarket's CLOB and subscribes to the token IDs for the markets you've enabled. Orderbook updates stream back in roughly 25ms. For order placement, the bot signs L2 transactions locally with your Polygon wallet key and sends them through the CLOB API. No middlemen, no custodians, your key stays in your local secrets directory.
Does it handle Polygon gas fees automatically? +
Yes. Polygon gas is subtracted from every edge calculation before the bot decides to fire. Current gas costs run roughly $0.05 to $0.15 per transaction, which is trivial for large trades but can eat a small trade entirely. The bot applies a configurable gas buffer so edges are always net-of-gas. You can also set a minimum stake to make sure gas is amortized properly.
Can I use it to arb Polymarket against Kalshi? +
Yes, and this is the main use case. The cross-venue WS arb engine watches the same event on both venues. When prices diverge past your configured threshold (with Kalshi fees and Polygon gas subtracted), it fires both legs simultaneously: buy Yes on whichever venue is cheaper, sell Yes on whichever venue is richer. Per-pair cooldowns prevent re-executing the same pair while the market is still digesting your fills.
What wallet setup do I need? +
You'll need a Polygon wallet (same keys as Ethereum, different network) funded with USDC.e for trading and a small amount of MATIC for gas. Most users keep a dedicated hot wallet for bot trading with a reasonable balance, not their main treasury. The bot reads your private key from the local secrets directory and signs CLOB orders locally. Nothing ever leaves your machine except the signed payload.
Can I paper trade on Polymarket? +
Yes. Paper trading runs the full pipeline (WebSocket feeds, edge detection, strategy selection, risk checks) against live Polymarket data but skips the CLOB submission step. You get simulated fills based on current bid/ask depth, realistic gas-cost accounting, and a paper P&L view. Run paper mode for a week before flipping live_execution=True and risking real USDC.
Related reading: Best Polymarket Trading Bot 2026, Kalshi vs Polymarket arbitrage. Also trading Kalshi? See our Kalshi trading bot page.