Live map · US equities and FX
Stock market heatmap
A price table tells you what moved. A heatmap tells you what moved together. Each tile is a company sized by market value and coloured by its change on the day, grouped into sectors.
S&P 500 by sector
Green is up, red is down, and the size of each tile is its weight in the index. Apple moving one per cent shifts the map far more than a small-cap doing ten.
How to read it
- Look at blocks, not tiles. One red company is noise. An entire sector block red while the rest is green is rotation — money leaving one part of the market for another.
- Uniform colour means macro. When everything is the same shade, the move is not about companies at all. It is a rate decision, an inflation print or a risk event, and it will usually show up in currencies and bonds too.
- Only trust it during cash hours. The map is built from regular-session trades, 09:30 to 16:00 New York time. Outside that window it is showing you the last print, not the current state, and pre-market moves in a handful of names can make it look far more decisive than it is.
Currency strength
The same idea applied to FX: each cell is one pair, coloured by its move. Reading across a row shows whether a currency is strong against everything or just against one weak counterpart — a distinction a single pair quote hides completely.
Unlike equities, the currency market never closes between Sunday evening and Friday evening. What changes is depth: the map is most meaningful during the London–New York overlap and least meaningful in the thin hours after the New York close, when a small order can paint a misleading colour.
The eleven blocks, and what drives each
The heatmap groups companies using the GICS classification: eleven sectors, each responding to a different force. Knowing which is which turns a wall of colour into a readable statement about the day.
| Sector | Weight in the S&P 500 | Usually reacts to |
|---|---|---|
| Information technology | Largest | Rates, earnings, AI sentiment |
| Financials | Large | Rate decisions, yield curve |
| Health care | Large | Regulation, trial results |
| Consumer discretionary | Large | Retail sales, confidence data |
| Communication services | Medium | Advertising demand, platform news |
| Industrials | Medium | Manufacturing surveys, trade policy |
| Consumer staples | Medium | Defensive flows, input costs |
| Energy | Medium | Crude oil, OPEC decisions |
| Utilities | Small | Bond yields, defensive flows |
| Real estate | Small | Mortgage rates |
| Materials | Small | Commodity prices, Chinese demand |
Two of these are the market's mood ring. When utilities and consumer staples are the only green blocks on the map, money is moving into safety — those are the sectors people buy when they want dividends and predictable demand rather than growth. The reverse, technology green and utilities red, is the risk-on version of the same signal.
When the map is telling you nothing
Three situations produce a heatmap that looks informative and is not.
- Outside 09:30–16:00 New York time. The colours freeze at the closing values. A map checked at breakfast in Europe is showing yesterday.
- Half-day sessions. The US market closes at 13:00 on the day after Thanksgiving and on Christmas Eve. Volumes are a fraction of normal and the percentages exaggerate wildly.
- Index rebalancing days. When the S&P committee adds or removes companies, funds tracking the index must trade regardless of price, producing moves that mean nothing about the businesses involved.