Money flow is the dollar value of Yes bought minus No bought in a market, per hour, by traders who crossed the spread. On Nimb, the market panel shows it as a bar chart and a sentence such as "$333k more went to No than to Yes over the past week", so you can see which side pushed the price.
What is money flow?
Money flow is signed taker flow: the dollar value of Yes bought minus the dollar value of No bought, per hour, counting only traders who crossed the spread.
Every trade has two sides. The maker left an order resting in the book; the taker came along and accepted it. Takers are the ones in a hurry, so their direction is the best simple measure of pressure. When a taker buys Yes, or sells No (which amounts to the same view), the dollars count towards Yes. When a taker buys No, or sells Yes, they count towards No. Flow is one of the three inputs to market reading, alongside price and holders.
How do I read the money flow chart?
In the market panel, the section is labelled "Money flow · Yes buying minus No buying, per hour". It has three parts.
The sentence. For the timeframe you chose, for example:
$1.2M traded over the past week. Traders who crossed the spread bought $333k more No than Yes.
The first figure is Polymarket's total volume for the outcome. The second is the net taker flow. In plain terms: $333k more went to No than to Yes over the past week.
The chart. 72 bars, one per hour, for the last three days. Green bars above the centre line are hours when more money bought Yes; red bars below are hours when more bought No. The thin dark line over the bars is the Yes price over the same 72 hours, so you can see whether the price followed the money.
The table. Flow over three fixed windows, whatever timeframe the map is on. An illustrative market:
| 12H | 24H | 3D | |
|---|---|---|---|
| Price | −1.2 pts | −3.1 pts | −3.5 pts |
| Buy (Yes side) | $18k | $52k | $160k |
| Sell (No side) | $41k | $118k | $240k |
| Delta | −$23k | −$66k | −$80k |
Read it left to right. Over 3 days, takers put $80k more on No than on Yes, and the price fell 3.5 points. Most of that, $66k and 3.1 points, came in the last 24 hours. Flow and price agree, and the pressure is recent.
What does it mean when flow and price disagree?
Usually one of four things, and the chart rarely tells you which:
| Pattern | Possible reasons |
|---|---|
| Strong Yes buying, price flat | A large seller or market maker is absorbing the buying with resting orders; or the buying came in small pieces against a deep book. |
| Price up, net No buying | Makers moved their quotes up (on news, say) and takers sold into them; price can move without taker flow. |
| Big flow in one bar, nothing either side | One large order. Check the holders: it may be one wallet. |
| Flow flips sign hour to hour | Two-sided trading with no clear lean; the net is noise. |
In the panel, a short tag can mark the same disagreement over 24 hours, when the market traded more than $2,000.
Is money flow a signal to follow?
No, not on its own. Flow describes what already happened. By the time a bar is on the chart, the price has usually absorbed it. Following flow means buying after others have bought, often at a worse price.
Where flow helps is in market reading, as a check: does the money back the move, or did the price drift on almost nothing? If you think you see something the market has missed, that is what Nimb's docs call alpha, and most apparent edge in flow turns out to be noise or fees. Large flows are also often one wallet, so read flow next to holders and wallet lines.
"Smart money" is a common search term for following large traders. Nimb does not label any wallet or flow as smart: a big position shows conviction or size, not skill.
How does Nimb compute money flow?
- Nimb reads the market's trades from Polymarket's public trades endpoint for the past 30 days. This returns taker fills.
- Each trade's dollar value is shares × price.
- A taker buying Yes or selling No adds to the Yes side ("Buy"); a taker buying No or selling Yes adds to the No side ("Sell").
- Trades are grouped into hourly bins in UTC. Delta = Yes side − No side.
- The sentence, chart and table sum those bins over the window shown.
Nimb's own tests checked this. Ranking markets by their flow-based dollars gives almost the same order as Polymarket's own volume (Spearman rank correlation 0.97). But taker-only dollars come to about 0.40× Polymarket's volume figure, which counts both makers and takers. That is why Nimb uses Polymarket's totals for "$ traded" and keeps taker flow only for direction.
What can money flow not tell you?
- The future. Flow is backward-looking. Positive flow last week does not predict next week's price.
- Who traded. $200k of Yes buying can be one wallet or two thousand. Check the holders.
- Why. Taker buying can be a hedge against a position elsewhere, a market maker rebalancing, or a bot.
- Maker intent. Makers shape the price by moving their quotes. That shows in the price line, not in the bars.
- Very old trades. The panel covers 30 days at most; the chart, three days.
See also how to read a price chart, the other five checks in how to read a market, and the glossary.
From reading to execution
In reading the market, use flow to judge how much money stands behind a move, not as a cue to join it. When the reading is done, the order ticket at the foot of the panel shows what your order buys and what it needs to break even.
Last reviewed 2026-11-07 · Data from Polymarket · Not financial advice · Nimb is not affiliated with Polymarket.