Footprint charts for NinjaTrader 8

A footprint chart — also called a volumetric or cluster chart — draws each bar as a column of price levels rather than a single body and two wicks. Beside every price it prints how much volume actually traded there, split by which side of the spread the trade happened on.

That split is the whole point. When a trade prints at the ask, a buyer paid the spread to get filled immediately. When it prints at the bid, a seller did. Volume alone tells you how much business was done; the bid/ask split tells you who was in a hurry.

Everything else on a footprint chart is arithmetic on those two numbers. Delta is one subtracted from the other. An imbalance is a ratio between them. Absorption is a large number for one of them with no resulting price movement. Read the two columns and the rest follows.

Two bars can close at the same price after the same range and mean completely different things. One rallied on steady buying that met no resistance. The other rallied into a wall of resting sell orders that absorbed every buy without giving ground. On a candlestick chart they are the same green bar.

Reading the bar's internals is how you tell those apart while the bar is still forming, rather than two bars later when price has already told you.

An imbalance marks a price where trade was heavily one-sided. The comparison is made diagonally — buying at one price is compared against selling one tick below it — because that is how the two sides actually meet in the book. A buyer lifting the offer at 4501 is competing with a seller hitting the bid at 4500.

When one of those numbers is several times the other, the level is flagged. A ratio of 3:1 is a common default; the right threshold depends on the instrument and the timeframe, and a setting that flags every second level tells you nothing.

Stacked imbalances — several consecutive flagged levels in the same direction — are read as a sign that one side ran through the other rather than trading with it. They frequently mark levels price returns to later.

Absorption is the opposite pattern. Aggressive orders keep arriving at a price, the volume printed there grows large, and price does not move. Someone is filling all of it with resting limit orders.

It matters because it inverts the usual reading. Heavy buying normally lifts price; heavy buying that fails to lift price means the buyers are being handed inventory by someone willing to sell everything they ask for. When the buying finally exhausts itself, there is nothing left to hold the level up.

Absorption is read at the extremes of a move rather than in the middle of one, and it is a reason to expect a turn rather than a signal to take one.

Delta is ask-side volume minus bid-side volume: a single number for how much more aggressive one side was than the other. Positive delta means buyers paid the spread more often. It can be measured per price level, per bar, or accumulated across a session.

The reading that gets the most attention is divergence. Price makes a new high while cumulative delta does not — the move is being carried by fewer aggressive buyers than the one before it. That is a warning about the quality of a move, not a prediction about the next one.

Delta is also frequently misread. A large positive delta on a bar that closed lower is not a broken indicator; it is buyers being absorbed, which is the point.

An auction is described as finished when the extreme of a bar traded on one side only — the high printed with buying and no selling above it, or the low with selling and nothing beneath. When both sides traded at the extreme, the auction there was left unfinished.

Unfinished business at a high or low is watched because price often returns to complete it. It is one of the few footprint readings that gives a specific level rather than a general condition.

The point of control — the price with the most volume in a bar or a session — is read the other way round: as the level both sides agreed on, and therefore one that tends to attract price back to it.

Most footprint tools can display a running set of per-bar statistics beneath the chart. Which of these you watch depends on what you trade, and displaying all of them at once is usually a way of watching none of them.

A footprint cannot be built from OHLC bars. It needs every individual trade, with the bid and ask at the moment each one printed, which means a data feed that provides real per-trade data rather than tick counts.

In NinjaTrader 8 that has two consequences. Live charts build their footprint from the incoming stream. Historical bars have to be reconstructed, and that requires Tick Replay to be enabled on the chart — without it the historical portion cannot show a bid/ask split, because the information was never in the bar data.

Tick Replay is expensive. It reprocesses every trade in the loaded range at startup, so loading many days of tick data across several charts is the usual reason a workspace becomes slow. Loading fewer days is almost always the fix.

NinjaTrader 8 ships with a volumetric bar type that shows volume at price with a bid/ask split, and it is genuinely usable. What third-party tools add is generally the analysis layer on top of it: configurable imbalance rules, absorption and exhaustion marking, session statistics, alerting, and control over what is drawn at which zoom level.

Whether that layer is worth paying for depends entirely on whether you will act on what it marks. A trader who does not yet read the built-in volumetric bars will not be helped by more colours on them.