Hindsight Markets / Glossary

How to practice tape reading

Updated 23 October 2026 · By Hindsight Markets

You practise tape reading by watching real time and sales and Level 2 on the kind of stock you trade, a little slower than live, and checking each read against what happened next. A replay of a real past day lets you run the same minute again until the read comes quickly. The four drills below are real moments from our data, with the numbers to check your read against.

What to watch

• Where the prints land. On time and sales, prints at the ask mean buyers are paying up; prints at the bid mean sellers are hitting bids.
• The size and the pace. A burst of prints after a quiet stretch says more than any single print.
• The size waiting in the book. On Level 2, a large order at one price is a wall. Watch whether it is being taken, refreshed or pulled.

Drill 1: the wall that gets taken

OLOX, 21 October 2026, in the pre-market. An offer at 1.18 had been on the book since 8:00 a.m. At 8:35:38 a.m. it peaked at 165,131 shares, about 11.7% of the float, spread across several exchanges. At 8:36:04 trades began printing at 1.18, and in 2.7 seconds 115,532 shares traded there. At 8:36:18 a buyer swept 97,921 shares from 1.20 to 1.22.

The read to practise: the size at 1.18 shrinking print by print, and what the bid does underneath it. Run it at half speed and call it before the offer is gone.

Drill 2: the same read, the other way

POM, 21 October 2026, 2:22 p.m. An offer of 52,316 shares appeared at 1.60. At 2:24:27 buyers took 10,123 shares of it on Nasdaq, stopped, and the price fell back to 1.58. At 2:25:57 they came back, 31,745 shares traded at 1.60 in 2.5 seconds, and the stock reached 1.78 at 2:27 before falling to 1.15 by the 2:34 pause.

The read to practise: a first attempt at a wall that fails, and the second that does not. The minute-by-minute book is on why your limit order didn't fill.

Drill 3: the wall that is pulled

POM again. During the pause from 2:34 to 2:39 p.m., a bid built up at 1.20 and peaked at 81,846 shares a second before the reopen. The stock reopened at 1.26, and by 2:42:10 that bid was gone, pulled rather than traded through.

The read to practise: size in the book is an offer, not a promise. A wall that leaves as the price comes near it was never support.

Drill 4: the sweep and the auction print

POM reopened from a pause at 10:30:35 a.m., and the reopening auction printed 32,171 shares at 1.55 on Nasdaq in one trade. About five seconds later a buyer swept 32,469 shares through nine price levels, from 1.63 to 1.71.

The read to practise: a big print at a reopen is the auction matching the orders that waited, not one buyer. A sweep, many levels taken in a fraction of a second, is someone who wants size now.

How to run a drill

1. Jump to a minute before the moment and pause.
2. Say what you expect, out loud or in a note: will the wall hold, will the price get through?
3. Play at half speed. Hide prints under a minimum size and highlight the large ones, so the blocks stand out.
4. Check your read against what happened, then go back and run it again at normal speed.
5. Place an order the second time, and see where it would have filled.

More on what the book and the tape show in a replay is on Level 2 and tape reading practice.