The short answer: Level 2 market data shows every active bid and ask from every market maker and ECN — not just the best price, but the full stack of who’s quoting what size at which levels. Level 1 tells you where the market is. Level 2 tells you who’s holding it there and whether they’re serious. That distinction is the whole game for active intraday traders.
What Level 1 Leaves Out
Level 1 gives you the best bid and the best ask. That’s the top of the book — the single best price from each side. If the best bid is $14.80 and the best ask is $14.82, that’s all Level 1 shows. You see the spread; you don’t see what’s behind it.
Level 2 shows you the rest of the order book: every price level below the best bid and every price level above the best ask, with market maker identifiers and size at each level. The difference between a thin book and a deep one is invisible in Level 1. In Level 2, it’s immediately obvious.
For swing traders holding positions for days and sizing off daily charts, Level 1 is enough. For active intraday traders where a few cents on the fill and a few seconds on the entry can swing a trade from profitable to breakeven, Level 2 is the read you’re actually making decisions from.
The Columns That Matter
Scanz Level 2 runs in two views. In QuickView, click any ticker and select the Prints & L2 tab — the Depth panel appears on the left, Time & Sales on the right. For more room, right-click any ticker and Open in New Tab to get the full Montage view, where the Level 2 tab shows three panels side by side: Book Summary, Depth, and Log.
In both views, each row in the Depth panel shows the same columns: TIME (when this market maker last updated their quote), MM (the market maker or ECN identifier), SIZE (displayed shares, in round-lot units), BID and ASK (their quoted price on each side).
What to watch:
SIZE is the number you’re reading for. But read it critically — displayed size is what the market maker chose to show, not necessarily what they’ll trade. Real size and fake size look identical in the book. The tape (Time & Sales) is how you distinguish them.
TIME tells you when the quote was last refreshed. A stale timestamp on a large bid means that market maker hasn’t updated their quote recently — they may have already traded through it, moved on, or pulled the quote entirely by the time you’re looking at it.
MM identifiers — BATS, EDGX, MEMX, IEX, NQEX, ARCA — tell you which venue is quoting. Recognizing the regular participants on a specific stock helps. Some names are predominantly NASDAQ-quoted; others have heavy ARCA or BATS presence. The Log panel in Montage tracks every quote change (Raised, Lowered, Opened, Closed) by market maker, which gives you a running read on who’s active.
Reading Intent: Where the Size Is and Whether It Holds
The useful question with Level 2 isn’t “how big is the bid?” It’s “does that bid hold when price tests it?”
A bid with 50,000 shares displayed at $14.80 looks significant. Whether it’s real comes down to what happens as price approaches it. There are two scenarios:
Scenario A: Price ticks down toward $14.80. The bid holds across multiple prints. Time & Sales shows buyers stepping in at the bid — print after print hitting at $14.80, and the bid staying put. That’s a buyer holding ground. The level has real demand behind it.
Scenario B: Price ticks toward $14.80. As it approaches, the 50,000-share bid starts flickering — disappearing and reappearing, or shrinking from 50,000 to 10,000 as price gets close. That’s a head-fake. The trader posting that size doesn’t want to buy — they want to create the appearance of support to attract buyers ahead of them so they can sell into the buying. Pull and replace is one of the most common patterns in active stocks.
The only way to tell the difference is to watch the Time & Sales alongside the book. The book shows intent; the tape shows whether intent is real.
Book Summary vs Depth: Two Ways to Read the Same Data
The Montage Book Summary panel aggregates by price level. Instead of showing each market maker separately, it shows how many market makers are quoting at each price, and the total size at that level. Five market makers each quoting 1,000 shares at $14.80 shows as # MM'S = 5, SIZE = 5,000. One market maker quoting 5,000 shares shows the same total size but as # MM'S = 1.
That distinction matters. Five separate market makers quoting the same price are more likely to represent genuine demand than a single participant. A wall built by one firm can be pulled instantly. A level where five firms are quoting takes more coordination to collapse.
Use Book Summary for the macro read — where is the real concentration of the book? Then drop into the Depth panel to see the per-market-maker detail and the Log for the real-time action stream.
What the Log Shows That Everything Else Misses
The Log in the Montage Level 2 tab is the event stream for the order book. Every quote action generates a row: which market maker, which side (Bid or Ask), and what happened — Raised, Lowered, Opened, or Closed.
Watching the Log during an active trade tells you things the static Depth panel doesn’t. If you see the ask side logging a series of “Lowered” events — multiple MMs bringing their offers down — that’s the ask stack collapsing ahead of a move. Sellers are stepping down to find bids. Aggressive buyers are about to clear the offer.
The inverse — a series of “Raised” events on the bid side — means buyers are getting more aggressive. Combined with Time & Sales showing prints at the ask, that’s the setup being confirmed in real time.
Pairing Level 2 with Time & Sales
The two panels answer different questions. Level 2 shows what’s posted. Time & Sales shows what got done. Together they’re far more informative than either alone.
In Scanz, the Prints & L2 tab in QuickView puts both in the same view — Depth on the left, Time & Sales on the right. In Montage, Time & Sales runs as a persistent panel in the upper-right while the full Level 2 view occupies the bottom tab.
The read to develop:
When you see a large offer in the book (say, 100,000 shares at $15.00) and Time & Sales is printing @Ask repeatedly — buyers are working through that wall. If the wall absorbs print after print and the offer keeps refreshing at the same price, that seller is real and well-supplied. If the prints hit and the offer starts thinning — 100,000 becomes 80,000 becomes 40,000 — the wall is being consumed, and price is about to clear it.
When the same offer prints get hit at $15.00 over and over but the SIZE column barely moves, you’re looking at an iceberg order. The book shows 500 shares; 50,000 shares are hidden behind it. The tape tells you — you see print after print at the same price while the displayed size barely changes. A persistent level absorbing more flow than the book shows is almost always hidden size.
Conditions Where Level 2 Misleads
Level 2 is most informative when the book is liquid and active. There are conditions where it’s less reliable:
Pre-market and after-hours: Many market makers don’t quote outside regular hours. The pre-market book is a fraction of the regular-hours book. Don’t size decisions based on what Level 2 shows at 8am — the book you see at 9:30am will be completely different.
Very low-float stocks: In thin names, a single large participant can dominate the entire book. One market maker’s behavior tells you their positioning, not the stock’s supply/demand balance. The tape becomes more important and the book becomes less reliable.
The final minutes before close: Market makers begin closing their quotes in the last 5–10 minutes of the session. The Log will show a parade of “Closed” events. Liquidity dries up fast. Don’t try to fill large size at 3:58 PM based on what the book looked like at 3:50.
Frequently Asked Questions
What is Level 2 market data? Level 2 market data shows the full order book — every active bid and ask from every market maker and ECN, at every price level, with the size each participant is quoting. Unlike Level 1 (which shows only the best bid and best ask), Level 2 reveals the depth and distribution of supply and demand behind the top-of-book price.
How do you read Level 2 data? Read it in three layers: the Depth panel shows each market maker’s current quote; the Book Summary aggregates size by price level so you can spot concentration; the Log tracks every quote change in real time so you can see the book thickening or thinning before price moves. Pair all three with Time & Sales to confirm whether displayed size is real.
What is the difference between Level 1 and Level 2 data? Level 1 shows the single best bid and best ask — the top of the order book. Level 2 shows every bid and ask at every price level, with market maker identities and size. Level 1 tells you where the market is trading. Level 2 tells you what’s behind that price and how much depth exists on each side.
How do you spot a fake wall in Level 2? A fake wall is a large displayed size that disappears as price approaches it. Watch what happens as price tests the level in Time & Sales: if the bid or offer flickers, shrinks rapidly, or gets pulled entirely before price touches it — that’s a head-fake. Real size stays through the test. The pull-and-replace pattern (size disappears as price approaches, then reappears at a worse level) is common around round numbers and key technical levels.
What is an iceberg order and how do you detect it in Level 2? An iceberg order hides the bulk of its size — only a small visible portion appears in the book. You detect it on the tape, not the book: if Time & Sales shows repeated prints at the same price level while the Level 2 displayed size barely moves, hidden size is being filled behind the visible quote. The book shows 500 shares; the tape shows 20,000 shares printing. That’s an iceberg.
Does Scanz include Level 2 market data? Yes. Scanz includes Level 2 in both QuickView (the Prints & L2 tab) and the full Montage view. Montage shows three Level 2 panels side by side: Book Summary (aggregated by price level), Depth (per-market-maker detail), and Log (the real-time event stream of every quote change). Time & Sales runs alongside Level 2 in both views.
When is Level 2 most useful for day traders? Level 2 is most useful during the regular session (9:30 AM–4:00 PM ET) when the book is fully populated. It’s particularly valuable during the first hour of trading when positions are being established, and around key price levels (prior highs, round numbers, VWAP) where the competition between buyers and sellers is most visible.
Scanz includes full Level 2 in every plan — QuickView for one-click access from any scan result, Montage for the complete Book Summary, Depth, and Log view alongside your chart. See plans and pricing. No commitment required.