Footprint charts: reading order flow inside every candle

A classic candle summarises a period with four prices: open, high, low, close. It tells you where price went, not how. A footprint chart opens the candle up and shows what happened inside: at every price level, how much traded and, crucially, who was the aggressor. It is the core tool of order-flow analysis.

Aggressors and passive orders

Every trade has two sides. One was waiting in the order book with a limit order: the passive side. The other came to take it with a market order: the aggressor, who accepted paying the spread to be filled immediately.

• An aggressive buyer “lifts the offer”: the trade prints on the ask.
• An aggressive seller “hits the bid”: the trade prints on the bid.

The footprint counts these two flows separately at each price. That is what the Bid × Ask mode of the Bullmarket terminal shows: aggressive selling on the left, aggressive buying on the right.

Delta: who won the candle?

Delta is aggressive buy volume minus aggressive sell volume. Positive delta means urgent buyers dominated; negative means sellers did. Cumulative delta (CVD) adds the deltas candle after candle and shows the underlying trend in aggression.

Delta becomes really interesting when it disagrees with price: an up candle with negative delta, or a new high while cumulative delta falls (divergence), suggests the rise is driven not by aggressive buyers but by sellers stepping away — a more fragile advance.

Imbalances

An imbalance flags that one side was far more aggressive at a precise spot. It is computed diagonally, because an aggressive buyer pays the ask, which sits one tick above the bid:

A 3× (300%) threshold is the most common; the terminal lets you pick ×2, ×3 or ×4. Several imbalances stacked on consecutive prices (“stacked imbalances”) often form a zone buyers (or sellers) will defend when price comes back.

Four patterns worth knowing

Absorption

Heavy aggressive selling at a level, yet price stops falling. Someone is soaking up all those sells with passive orders, often a large buyer. At a low, it is a classic sign of a potential reversal.

Exhaustion

The opposite: volume dries up at the top of a rising candle — the last buyers are done buying. Very thin volume at the extreme price means there is no fuel left.

Unfinished auction

When a candle’s high (or low) shows volume on both sides instead of almost nothing on one side, the auction is not “finished”. The market often comes back to test that level later.

Candle point of control

The price with the most volume inside the candle. A close far from it in the direction of delta confirms the move; a close drifting back to it shows indecision.

Setting up your footprint

• Price step: too fine and each candle holds 200 unreadable rows; too coarse and information is lost. Aim for 20–40 rows per candle (the terminal does this automatically).
• Timeframe: 1 minute for scalping, 5–15 minutes to read key areas with less noise.
• Context: a footprint is never read alone. It matters near a key level — yesterday’s high, the POC or value-area edges, large liquidity in the order book.

Going further

Open the terminal on BTC/USDT at 1 minute during an active session (the Wall Street open, a macro data release) and watch how delta and imbalances behave at highs and lows. Then test your reads risk-free in the trading simulator.