
Spot the Move. As It Happens.
Real-time options flow, drawn as a live line. See who's buying, who's selling, and which side they're taking as it happens.
Read the flow before the price.
Dealer hedging, in dollars
Every options trade leaves a market maker holding risk they have to offset in the stock. Heat prices that offset on each print and sums it across the session, one running total per cohort.
The unit is dollars of underlying, not a score or an index. Each step is the option's delta times one hundred times spot times contracts, signed by the way the dealer gets pushed. The formula is published in full.

Retail Proxy, not account data
Retail Proxy includes only verified OPRA SLAN single-leg, non-ISO auction prints. It isolates a strict execution pattern in Heat, not the account behind the trade.
Named classifier, published limits
Each print is assigned a side by the Lee-Ready quote rule, which the literature puts at eighty to eighty-five percent on clean single-leg trades. Prints we cannot call are dropped, not guessed at.
The front expiration, split out
One curve carries only the nearest expiration, which on an expiry day is the whole 0DTE book. When it does the work and the whole-market line does not, the move runs on contracts that die at the bell.

Six levels and your own alerts
Call wall, put wall, gamma flip, both edges of the expected-move band and the prior close, drawn on the flow chart's price scale. Your own price alerts sit alongside them, labelled, on the same axis.
One strict proxy, one honest complement
Retail Proxy can overlap All and Next Expiry. Other Flow is derived as All minus Retail Proxy; it is not a label for institutional flow.
The cockpit around the chart.
The bar above sets what you see. The rail beside keeps your symbols, alerts, and flow one click away.
The top bar is built for Heat. Switch between Total and Put/Call, turn the cohorts you care about on or off, and overlay your alerts, key levels, or extended hours, all without leaving the chart. Down the right rail sit your Watchlist, your Alerts, and a full Ticker Details dashboard, each one tracking whatever symbol you have active.
More EssentialsThe same bar and the same rail, on every product.
Most of the market now moves in real time.
of SPX options volume expires the same day. The flow plays out in one session.
of short-dated options volume is retail. Heat splits it out as its own line.
of all US options volume is now 0DTE, up from 21.5% a year earlier. The shift is accelerating.
Source: Cboe Global Markets, the NYSE, and the OCC, 2025 data.