The bid ask footprint is the most information-dense way to display an order flow chart, and the one most traders settle on. Every price row carries two numbers: aggressive selling on the left, aggressive buying on the right. Learn to read that pair fluently and you can see, tick by tick, which side was crossing the spread to get filled.
This is the display type in depth. If you want the big-picture view of what a footprint is, start with the footprint chart guide; here we stay on the bid x ask layout and how to actually read it.
What the two numbers mean
Each row of a bid x ask footprint sits at one price level and shows two totals side by side, usually written bid x ask:
- Left number = volume traded at the bid. These are aggressive sellers, market sell orders hitting resting bids.
- Right number = volume traded at the ask. These are aggressive buyers, market buy orders lifting resting offers.
So a row reading 120 x 340 means 120 contracts were sold aggressively and 340 were bought aggressively at that price. Buyers were the aggressors there by almost three to one.
This is the part that trips everyone up at first, so burn it in: volume “at the ask” is buying pressure, volume “at the bid” is selling pressure. The number on the right is the buyers. It feels backward until it clicks, and then it never leaves you.
Why bid and ask and not just “buys and sells”? Because every trade has a buyer and a seller. What the footprint records is who was aggressive, who crossed the spread and demanded a fill right now. The passive side sat on a limit order and waited. The bid x ask split is a record of aggression, not of who is long or short.
Reading a single bar top to bottom
Take one 5-minute bid x ask candle and work down the rows. Here is a small ES bar for the sake of example:
| Price | Bid x Ask |
|---|---|
| 5,404 | 60 x 410 |
| 5,403 | 90 x 520 |
| 5,402 | 140 x 300 |
| 5,401 | 380 x 260 |
| 5,400 | 620 x 180 |
Now the read:
- Find the heavy rows. 5,400 and 5,401 dwarf the rest. That is where the bar spent its energy, the intrabar point of control.
- Check who owned them. At 5,400 the split is
620 x 180, sellers hitting the bid three to one. At 5,401 it is380 x 260, still seller-leaning. The volume concentrated at the bottom of the bar, and sellers were aggressive there. - Read the extremes. The top row, 5,404, shows
60 x 410, almost pure aggressive buying with nothing selling above. That is an unfinished look at the high (more on that in unfinished auctions). - Sum the delta. Add ask minus bid across every row. This bar nets slightly positive despite all that selling at the low, because buyers took over on the way up. A green candle, then, but one that had heavy sellers absorbed near the bottom.
That last step is where the bid x ask layout earns its keep. The candle only shows you a green body. The footprint shows you that the low was a fight, sellers threw 620 contracts at 5,400 and price still turned up. Somebody was buying every one of those passively.
The diagonal, quickly
When you compare the two sides to judge dominance, the meaningful comparison runs on the diagonal, not straight across a row. Aggressive buyers lift the offer at one price while aggressive sellers hit the bid one tick lower, so you pair the ask of a row against the bid of the row below it. When one diagonal side runs three times or more the other, that is an imbalance.
The bid x ask footprint is the only display that shows you this directly, both raw numbers are on screen, so you can eyeball the diagonal yourself. That is a big reason experienced readers prefer it. The full mechanics live in order flow imbalances; the point here is that only the two-number layout hands you the data to see them.
What good and bad reads look like
A few signatures you will see over and over on the bid x ask:
- Aggressive buying that pays off. Heavy ask volume (right side) climbing bar after bar, with price following. Buyers are crossing the spread and getting rewarded. Trend.
- Aggressive selling that fails. Big bid volume (left side) at a low, and price refuses to break. Someone passive is soaking it up. That effort-without-result signature is the heart of absorption trading.
- Two-sided churn. Rows where bid and ask are roughly equal, up and down the bar. Nobody is in control; this is balance, not a signal.
The skill is not memorizing these. It is getting fast enough at reading the two numbers that you notice when the split stops being even.
When to use bid x ask over the alternatives
The bid x ask footprint is the right default when you are learning to read flow and when you want maximum detail at decision points. Its cost is visual density; a fast NQ session can put a lot of numbers on screen.
The two other displays trade detail for speed. The delta footprint collapses each row’s two numbers into one net figure, cleaner to scan once you trust your reading. The volume footprint drops the side split entirely and shows total volume per row, best for seeing where trade concentrated without worrying about direction. Many traders run bid x ask as their primary and glance at the others for context. How to switch between them and tune the display is covered in footprint chart settings.
A practical rule I use: bid x ask on the timeframe I make decisions on, and a simpler display on the timeframe I use for context. Detail where it counts, speed where it does not. It all ties back to the wider read laid out in the order flow trading guide.
Frequently Asked Questions
What does bid x ask mean on a footprint chart?
It is the two-number layout where each price row shows volume traded at the bid on the left and volume traded at the ask on the right. Volume at the bid is aggressive selling; volume at the ask is aggressive buying. A row reading 90 x 250 had far more aggressive buying than selling at that price.
Is the left number buying or selling?
The left number is aggressive selling, volume that traded at the bid because market sell orders hit resting bids. The right number is aggressive buying, volume at the ask from market buy orders lifting offers. The intuition feels backward at first: buyers are on the right, sellers on the left.
Why do traders prefer bid x ask over the delta footprint?
Because it shows the raw numbers on both sides, so you can read the diagonal for imbalances and see the exact split at every price, not just the net. The delta footprint is faster to scan but hides the totals. Most readers use bid x ask at decision points and the delta footprint for quick context.
Does the bid x ask split show who is long or short?
No. It shows who was aggressive, who crossed the spread to get filled right now, not who is holding a position. Every trade has a long and a short; the footprint only records which side demanded the immediate fill versus which side waited passively on a limit order.