Polymarket Bot Tutorial · Chapter 20 of 32

Track Polymarket whale wallets and copy-trade top performers programmatically: identify profitable wallets via leaderboard and on-chain analysis, mirror their trades with size and timing rules.

By Harley Young, lead writer at Polymarkets.co.il. Last reviewed: May 2026.

What this chapter covers

This is chapter 20 of our 32-part series on building a Polymarket trading bot. We cover the topic in depth across the sections below. Body content for each section is being written and rolled out chapter-by-chapter; FAQ answers and references are already complete and reflect production experience from running our own trader.

  • Identifying profitable wallets
  • On-chain trade detection
  • Position sizing relative to the whale
  • Latency: how late is too late
  • Filters: only follow wallets with verified edge
  • Code: detect whale buy event, place sized copy

Identifying profitable wallets

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

On-chain trade detection

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

Position sizing relative to the whale

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

Latency: how late is too late

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

Filters: only follow wallets with verified edge

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

Code: detect whale buy event, place sized copy

This section is in active development. Want to be notified when it goes live? Contact us or watch the authors page.

Frequently asked questions

How do I find profitable Polymarket wallets to copy?
Polymarkets own leaderboard surfaces top wallets by PnL across multiple windows (week, month, all-time). Independent on-chain analytics tools (DeFiLlama, Dune dashboards) also rank Polymarket wallets. Pick wallets with verified profitability over months, not weeks - hot streaks reverse.
How do I detect a whale trade in real time?
Subscribe to Polygon transaction logs for the wallet address (web3.py / ethers eth_subscribe), filter for matchOrder calls on the Polymarket exchange contracts. Decode the event to get the market, side, and size. Latency: 2-10 seconds from on-chain confirmation to your bot reacting.
Can I copy a whales trade exactly?
Not exactly - by the time youve detected and submitted, the price has often moved. The realistic copy is "scale-in": take a fraction of the whales position over a few minutes after their trade, accepting the price degradation as the cost of copying. Sizing: 1-5% of their position size per copy.
What if the whale is wrong this time?
You lose. Copy trading inherits all the risk of the underlying strategy plus latency loss. The hedge is to copy multiple whales and treat each as a small portion of your portfolio - if 5 whales each have 60% win rate independently, the portfolio compounds. If you copy one whale with 60% win rate and concentrate, variance kills you.
Is copy trading prohibited on Polymarket?
No. Polymarkets terms allow viewing public leaderboards and trades. What is prohibited is multi-accounting (running multiple wallets as one person to circumvent limits). Copy-trading other peoples wallets from your single wallet is fine.
How do I size relative to a whale?
Bankroll-fraction sizing: never copy a single trade for more than 2-5% of your total bankroll regardless of how much the whale traded. Treat the whale signal as one of many, not as a sure thing. Whales with 10x your bankroll still lose - your relative drawdown is much worse if you size aggressively.