Education · Stage 5 · 02
The opening range
The high and the low of the first part of the session become the reference the rest of the day argues with. It is the most useful object on an intraday chart, and the most commonly misused — because the lines drawn beyond it are a completely different kind of thing.
Mak · 4 min read · Stage 5, article 2 of 8
What it is
Take the first stretch of the session and mark the highest and lowest price reached. That box is the opening range. How long a stretch is your choice, and the choice changes the object:
| Window | What you get |
|---|---|
| 5 minutes | Fast and noisy. A range built from the most chaotic minutes of the day. |
| 15 minutes | The common compromise: the first burst has passed, the range is still early. |
| 30 to 60 minutes | Slower and steadier. Less of the opening noise, and it is late in the morning before you have it. |
The one-hour version has its own name from market profile work: the initial balance. It gives you three numbers — a high, a low and a midpoint — and by around 10:30 the session has an agreed shape.
Why its edges actually matter
Not because the range is magic. Because it is obvious to everybody.
Everyone watching this market has the same two numbers by mid-morning. Which means orders collect around them: stops from people who are already positioned, entries from people waiting for a break. That is the mechanism from the stage on buying and selling, arriving in the real world — a level matters because instructions are resting there, not because the price is special.
This is also why the edges of the range behave, sometimes, like walls and, other times, like a trapdoor. Nothing about the line changed. What changed is whether enough passive orders were waiting on the other side to absorb what arrived.
Size is a description of the day so far
A first hour that produced a narrow range and one that produced a wide one are describing different mornings, and it is worth naming the difference before the day continues.
- Narrow — little disagreement so far. The day has not committed to anything, and the range is small enough that leaving it does not take much.
- Ordinary — the most common case, and the least informative on its own.
- Wide — a great deal has already happened. The move people are waiting for may already have occurred, and a break of a wide range asks for a lot more movement than a break of a narrow one.
The playbook this site is built on adds an observation worth keeping, and it is about behaviour rather than odds: a wide opening range is where breakout traders most often get caught, because the market has already spent the energy they are betting is still to come.
Where the boundaries between narrow, ordinary and wide sit depends on the instrument and on how volatile the period is. Measure it on your own market over a few weeks rather than importing a number: what you want is compared with its own recent mornings.
The part nobody says out loud
Platforms will happily draw lines at 50%, 100% and 200% beyond the range. They look exactly like the range's own edges: same style, same colour, same confident straight line.
They are not the same kind of object at all.
An extension is not support, not resistance and not a target. It is one hour of range multiplied by a number, projected into a place where nothing has traded.
That does not make extensions useless. They are a reasonable way to talk about how far this day has travelled compared with its own morning, which is a real question. It makes them a measuring stick rather than a level, and treating a measuring stick as a wall is how people end up defending a line the market has never seen.
The four things that happen next
Once the range is set, price can do exactly four things, and naming them in advance is genuinely useful because it stops you inventing a fifth in the moment:
- It leaves upwards and keeps going.
- It leaves downwards and keeps going.
- It tries to leave and comes back — the edge held.
- It never leaves at all, and the day stays inside the morning's range.
The fourth is more common than beginners expect and is the one nobody plans for, because every course is written about the first two.
And the honest closing note is one the playbook writes itself, in the middle of its own page about this: it is not true that this always works. The opening range is a reference, and a reference tells you where you are. It does not tell you what happens next.