Footprint Chart: The Bar Taken Apart
A footprint chart expands each price bar into rows, one for every traded price, showing how much volume executed there and splitting it by which side crossed the spread. It is the volume of a single bar taken apart, and it is an inference about urgency rather than a record of who bought.
How it works
A footprint chart is an ordinary bar with its inside shown. Instead of four numbers — open, high, low and close — the bar becomes a column of rows, one per traded price, each carrying the volume that executed there.
The rows are the whole idea. A candle gives the range a bar covered; the footprint gives where inside that range the trading happened, and how much at each price.
Each row is then split in two. Trades executed at the offer are counted as buying and trades executed at the bid as selling, so every cell holds a pair rather than one number.
That split is an inference, and worth saying plainly. Every trade has a buyer and a seller. The classification records which side crossed the bid-ask spread, not who bought.
Delta, imbalance and absorption
Delta is the difference between the two counts. Subtract selling from buying in a row for that row’s delta, or across the bar for the bar’s. Cumulative delta sums it across a session.
An imbalance is a row that is badly lopsided. One side substantially exceeds the other, usually measured against the adjacent price on the opposite side.
Every threshold for one is relative. What counts as lopsided depends on the instrument and the hour, so a number copied from elsewhere marks everything or nothing.
Heavy buying with no progress means somebody is selling. A row with far more executed buying than selling, at a price that did not move, says resting sell orders absorbed it. That is the clearest reading the chart offers, and still an inference.
It is also the reading most often applied afterwards. Once price has turned, the bar where it turned contains one; finding it there is not the skill.
In practice
Running one requires tick-level data with side classification. That is a paid feed on most instruments, plus a platform that renders it.
It is primarily a futures tool. Those markets run one consolidated tape, so every execution is counted once.
What you are looking at is the volume bar taken apart. Volume analysis gives how much traded; this gives where.
None of the detail survives to a higher timeframe. On a daily bar each row averages a session, and the sequence that produced it is gone.
And there is nothing to count across a gap. An opening gap is a stretch of prices at which nothing traded, so those rows do not exist.
It never tells you where the stop loss belongs. The grid describes what executed; a stop decides how wrong you are prepared to be.
Reading it quickly also means trading quickly. On this site’s shared 576-bar history a round trip costs 2% of a median bar’s range — a toll on every move scalping tries to capture.
Against its neighbours, the difference is what gets counted. The order book, shown as level 2 or depth of market, lists intent that can be cancelled.
The tape shows executions in sequence; the footprint shows the same ones organised by price. One is time order, the other is price order.
Learning to read one
Start by watching, not by trading. Pick one instrument, put its footprint beside its price, and follow it for several sessions before drawing a conclusion from it. The first job is calibration.
You are learning what normal looks like on that instrument. A row that is wildly lopsided in one market is unremarkable in another, and the same market changes character between the open, the middle of the day and the close.
Note where the heavy rows sit, then ask whether the price held. Write down what you saw. After a few sessions the answer stops being theoretical, because you have your own baseline instead of somebody else’s threshold.
Only then is it worth putting on a live decision. Reading a grid you have no reference for produces confident sentences about nothing.
What a footprint chart is not
- Not a record of who bought. Every trade has both sides; the split records who crossed.
- Not an order book. It counts completed executions, which cannot be cancelled.
- Not a signal. A lopsided row describes the last few seconds, not the next few.
- Not a higher-timeframe tool. Above a few minutes the rows blur into averages.
When it fails
In a quiet market the cells are too empty to read. Volume has to be spread across enough prices for the rows to differ. Inside a slow trading range each cell holds a handful of trades and the reader supplies the pattern.
- When the classification is backwards. A resting buyer filled at the bid — often market makers doing their job — is counted as selling, because the seller crossed.
- When size is being worked. An algorithm slicing a parent order produces steady two-sided rows that look like broad participation, by design.
- When the market gaps. Prices that never traded have no rows, so the grid is silent across exactly the move that mattered.
- When the reading arrives late. Absorption is obvious at the bar where price turned, ambiguous at every bar that looked the same and did not.
- When you are already positioned. Every imbalance then reads as confirmation, and a grid this detailed will confirm almost anything.
The original data
Eighteen videos carry “footprint” in the title; 346 carry “volume profile”. The scan of 31,760
titles in research/search-study-corpus.jsonl, logged in research/broker-coverage.json, puts their
medians at 21,420 and 7,947 views. Two magnifications of one dataset, and the coarser one — the one
that photographs, rather than the one you have to watch live — is covered nineteen times more often.
A round trip costs 45% of the smallest bar on that same history. That comes from
research/series-measurements.json via site/measure_series.py, and a tool used to trade small moves
has to clear a cost that is a large fraction of them. Use it to judge whether a level is holding, not
to predict which way the next bar goes.
Related
Order flow is the subject this page sits inside — 124 videos at a median of 14,001 views, and the footprint is one way of drawing it.
The tape is the same executions in time order rather than price order, which is why the two are usually read side by side.
Volume profile is the coarse version of the same count, stacked across a session rather than a bar, and where the value area comes from.
I went through a phase of wanting more resolution on everything, and the footprint is where that phase ended. There is a point where extra detail stops telling you more about the market and starts telling you more about your own attention. I can read one now and still be no clearer about whether to take the trade. What changed was using it to check a level I had already chosen, rather than to go looking for one.
— Michael Whitman
This page is educational, not financial advice. Test every idea on your own charts before risking money.