Playbook 03 · Slide 02 of 10 · Mechanics · How the Bracket Is Built · Step by Step

The 30-Min Bracket

How the opening range is constructed — bar by bar, minute by minute. Understanding the mechanics is essential before you can trade it.

Start

09:30

RTH open

End

10:00

Bracket set

5-Min Bars

6 bars

09:30 to 10:00

15-Min Bars

2 bars

09:30 to 10:00

09:30:00

RTH Opens — Bracketing Begins

The opening bell rings. Record the high and low of the first candle. On a 15-min chart, this is bar 1 (09:30–09:45). On a 5-min chart, this is bars 1–6.

Start

09:30 – 10:00

Tracking the Extremes

On each new bar, compare its high to the current bracket high. If higher, update. Compare its low to the current bracket low. If lower, update. The bracket expands until 10:00.

Expanding

10:00:00

Bracket Is Set

Two horizontal lines are drawn — one at the highest high, one at the lowest low. These lines stay on the chart for the rest of the session. They never move again.

Locked

10:00+

Read the Interaction

Watch how price behaves around the bracket lines. Breakout = trend day. Bounce = range day. The next 30–60 minutes confirm the day type.

Active

Bar-by-Bar Example (5-Min)

Bar 1 (09:30): High 5850, Low 5842 → Bracket = 5850 / 5842

Bar 2 (09:35): High 5848, Low 5840 → Low drops to 5840

Bar 3 (09:40): High 5855, Low 5843 → High expands to 5855

Bar 4 (09:45): High 5852, Low 5841 → No change

Bar 5 (09:50): High 5853, Low 5838 → Low drops to 5838

Bar 6 (09:55): High 5854, Low 5839 → No change

Final Bracket: 5855 / 5838

What the Bracket Tells You

Wide bracket (>20 pts): Volatile open. Expect a trend day or wide range day.

Narrow bracket (<8 pts): Compressed open. Expect a range day or slow grind.

Bracket near prior close: Neutral open. Wait for direction.

Bracket far from prior close: Gap-driven. Direction likely set pre-market.

⚠ Rule: The bracket never moves after 10:00. If price makes a new high at 11:30, the bracket high does NOT update. It's locked. This is what makes it reliable — it's a fixed reference point for the entire session.