Session opening range: a defined first hour, then a break

Research status: untested hypothesis. No backtest, paper or live results exist. Every threshold, period, R value and risk fraction is an untested candidate parameter, not a recommendation. This is not the same playbook as Range mean reversion, which fades a frozen daily range back to the midpoint.

The idea

Crypto trades all day, so “the open” is a definition we have to write down, not a bell we can hear. This playbook freezes the first hour of the UTC day as an opening range, then asks whether a later completed close through that high, with a stop back inside the range, is a testable breakout. The same clock that makes the range honest also makes this a research choice: 00:00 UTC is not a New York cash open, and a different session would be a different hypothesis.

IF–THEN rules

All times are UTC. Use completed 15-minute bars only.

1. Freeze at 01:00 UTC. From the four completed 15-minute bars that begin at 00:00, 00:15, 00:30 and 00:45, record high H, low D, width W = H − D (must be positive) and midpoint M. These don’t move for the rest of the UTC day.
2. Width filter: W must be at least 0.8 × the 15-minute ATR(14) computed at freeze time, and no more than 3.0 × that ATR. A tiny range makes a noisy break; a huge first hour often is the move.
3. Break: after 01:00, the first completed 15-minute bar whose close is above H + 0.05W is the signal bar. Do not trade inside the first hour, and do not trade a wick through H without the close.
4. THEN enter at the next bar’s first executable price, if all shared checks pass.
5. One attempt per UTC day. If the first signal fails the checks, or the trade exits, stop for the day. Don’t hunt a second break.

• Stop: M − max(2 ticks, 0.02W). Frozen. That sits inside the opening range, so a return to the middle invalidates the break.
• Target: H + W (the opening range’s height projected up). Frozen. Net reward must be at least 2R after costs. If the next open, or costs, remove that room, skip the day.
• Failure exit: a completed close back below H − 0.05W exits at the next open (the stop has priority).
• Time stop: the last exit opportunity is the 15-minute bar that begins at 20:00 UTC; if still open, exit at that bar’s close, or earlier if the time stop bar is still running at a scheduled event window (see shared filters).
• Size from the stop with the position-size calculator, at 0.25% of equity (untested modeling parameter). Results in R.

When NOT to trade

• The first hour is too narrow or too wide for the ATR filter, or W is not positive.
• No close through H + 0.05W before 16:00 UTC: that’s a missed day, not permission to loosen the close or chase a late spike.
• The next open gaps through the 2R target, or through the stop.
• Any shared no-trade filter fails.
• A short on a close through D is a separate hypothesis.

Common mistakes

• Trading the first-hour bars themselves. The range has to finish before it can be used.
• Entering on a wick over H and calling it a break. The rule is a close.
• Fading the same range toward M and also trading this break, then combining the records. That mixes Range mean reversion with this playbook.
• Redefining “the open” mid-test (New York, 08:00 UTC, weekend vs weekday) without calling it a new hypothesis.
• Moving the stop to D after entry “for room.” The invalidation is the midpoint, written in advance.

Hypothetical example (made-up prices)

Item	Value
Opening range 00:00–01:00 UTC	H 80.00, D 79.20, W 0.80, M 79.60
ATR(14) at freeze 0.50; 0.80 is inside 0.40–1.50	Width ✓
Signal close (10:45 bar)	80.10 (> 80.04) ✓
Entry (next open)	80.12
Stop: 79.60 − 0.02	79.58
Risk per unit incl. 0.02 costs	0.56
Target H + W	80.80 → net about 1.18 / 0.56 ≈ 2.1R

If it works: price reaches 80.80 before 20:00 UTC: about +2.1R. If it fails: price trades 79.58 and fills at 79.55: a little more than −1R. Or it closes back under 79.96 and exits on the next open, wherever that is. Missed day: no close through 80.04 before 16:00. Record the miss; don’t invent a late entry.

Ratigan Capital rules in this playbook

• Early Is Wrong: buying the first poke through H, before the close, is a different strategy.
• Patience as a Position: many UTC days never produce a close through the high.
• Never Average Down: a failed break is an exit, not a second try at a “better” open.
• Price Is the Only Truth: the clock is a research choice; the stop is still a price.

Why it can fail

The first hour can be quiet, then a later break is just a mid-day drift that returns to M. The first hour can also be the day’s whole range, so a late close through H is a late, thin probe. Weekend and weekday UTC opens can behave differently; if they do, lumping them together will muddy the test. Gaps around 00:00 UTC can distort W.

Pre-trade checklist

1. H, D, W and M frozen at 01:00 UTC from exactly four bars, width filter passed?
2. First qualifying close after 01:00 and before 16:00, no earlier trade today?
3. Shared filters clear?
4. Stop, target, time of last exit and size written; net ≥ 2R after costs?

Sources

• StockCharts ChartSchool: Support and resistance
• StockCharts ChartSchool: Average True Range (ATR)
• StockCharts ChartSchool: Price Channels
• Core rules for every playbook