Do it by hand first
Polymarket settles on a public chain and publishes its order books. Before paying anyone, spend a week doing this manually — it teaches you what the alerts should have been filtering for, and some people find that a watchlist of six addresses is all they ever needed.
- Pick a market you already follow. Whale watching in a category you do not understand produces noise you cannot interpret.
- Pull the large fills, and note the book they hit. Record the depth on both sides at the moment of the trade, not afterwards. A large fill into a thin book is a different event from the same size into a deep one.
- Look up the wallet’s history. Has this address traded this category before? Did price move after its previous entries, or did it arrive late?
- Wait for resolution and write down the outcome. This is the step everybody skips, and it is the only one that turns an impression into a record.
- Repeat for two weeks. A wallet that looks prescient over three trades is almost always luck.
What to ignore
- Notional size on its own. Opening an address takes a minute. A six-figure trade from a wallet with no history is a fact about somebody’s balance, not about the market.
- Profit leaderboards. They rank whoever has been luckiest in the sample. Useful as a list of addresses to investigate; worthless as a verdict.
- A single large trade near resolution. Late size often reflects someone closing rather than someone knowing.
- Round numbers. A clean $100,000 is usually a person with a round number in mind, not a calculated position.
Where the manual method stops working
It stops at breadth. Following six wallets across two categories is a pleasant habit; following the venue is a full-time job, and the trades worth seeing do not wait for you to check. That is the point where a ranking has to run continuously — and the point at which the question becomes which ranking, not whether one.
The criterion matters more than the plumbing. Why size is the wrong threshold sets out the alternative in full, and the comparison of the available tools covers who ranks on what.
Frequently asked
- Can I track Polymarket whales for free?
- Yes. The chain is public and every trade is visible. What you are paying for with a tool is the filtering and the continuity, not access to the data.
- How large is a whale trade on Polymarket?
- There is no fixed number, and any tool that gives you one is selling a size filter. The same amount is significant in a thin market and unremarkable in a deep one — which is why depth belongs beside the trade.
- Should I copy a whale’s position?
- Not directly. A large wallet can sit through a drawdown that would close your position at the worst moment, and the same trade at a different size is a different trade. The common failure modes are written up here.
- How long before a wallet’s record means something?
- Longer than feels satisfying. A handful of trades tells you nothing; the point at which a pattern separates from luck depends on how often the wallet trades, which is why continuous ranking beats occasional inspection.
Keep reading
- Polymarket whale tracker
The automated version of the method above.
- Polymarket tools
The rest of the instruments, including the free calculators.