A lopsided ratio of buying-to-selling volume (or vice versa) at a specific price level — a signal that one side is overpowering the other.
An Imbalance occurs when aggressive volume on one side of the market overwhelms the other at a specific price level. On a Footprint Candle, this appears as a large ratio between ask-volume and bid-volume at a given price — typically 3:1 or greater.
Types of Imbalance:
What it means for the market: a single Imbalance at one level is noise. But when Imbalances stack across consecutive prices — a Stacked Imbalance — it reveals institutional aggression that is unlikely to be accidental. That pattern is the strongest order-flow signal available.
The SPX context: SPXXL cannot observe raw price-level Imbalances on SPX (no centralized tape). The engine approximates Imbalance through momentum analysis: when the scoring engine detects a sustained, accelerating momentum score in one direction with expanding volume, it is reading the downstream EFFECT of what a Footprint trader would see as stacking Imbalances.
For 0DTE traders: when SPXXL's 6-Step Read shows the Imbalance proxy step as "confirmed," the engine is seeing the kind of one-sided aggression that, on a Footprint Chart, would light up as stacked buy or sell Imbalances. That is a trend-continuation signal — not the time to fade.
This entry is educational and uses SPX for illustration — it is not financial advice, and no outcome is predicted or guaranteed.
Three or more consecutive price levels showing a dominant buying or selling Imbalance — the institutional "footprint" that reveals large-lot aggression.
The real-time stream of buy and sell orders hitting the market — the raw aggression behind every candle, revealing who is in control before the chart shows it.
An advanced candle type that displays the volume transacted at each price level within the bar — showing the bid×ask split that a standard candle hides.
When passive limit orders absorb aggressive market orders WITHOUT price moving — a hidden wall that reveals large institutional resting liquidity.
When price makes a new high (or low) but the cumulative Delta does not — a signal that the aggression behind the move is exhausting.
The total number of option contracts traded during a given period — higher volume means more participants are actively buying and selling, which makes it easier to enter and exit positions at fair prices.