Day Trading Setups
Gap-and-Fill Continuation Scanner
Most traders blow up chasing the setup they missed, not the one in front of them.Jason Parker, Founder of Trading Habits
A session's opening gap either trades back to touch the prior close or it doesn't, and the size of the gap itself is genuine information about which is more likely.
Call it before the intraday bars play
Seven simulated days line up below with each genuine gap percent already visible, the same information you'd have premarket. Predict Fill or No-Fill on a row, then press play to run that day's genuine intraday bars against a dashed line at the prior close. The result rolls into a fill-rate table sorted by gap size.
Predict a row below, then press Play to run that day.
| Gap tier | Days | Filled | Genuine fill rate |
|---|---|---|---|
| Small (<0.5%) | 0 | 0 | — |
| Medium (0.5–1.5%) | 0 | 0 | — |
| Large (>1.5%) | 0 | 0 | — |
How it works
- Gap % is today's open against yesterday's close. Open minus prior close, divided by prior close, computed the instant the new day's open prints, before any intraday bar exists.
- Filled means a genuine price touch, not a guess. A gap up counts as filled the moment any bar's low trades back down to the prior close level. A gap down counts as filled the moment any bar's high trades back up to it.
- Three tiers sort every gap the moment it prints. Small is under 0.5%, medium is 0.5% to 1.5%, large is over 1.5%.
- Bigger gaps resist filling because they carry more genuine imbalance. A small gap is close to overnight noise a session absorbs quickly, a large gap reflects a genuine repricing serious enough to hold. The fill-rate table above should show that tier by tier as you scan more days.
Where this breaks
Fill odds are a tendency, not a same-day rule
Everything above describes a pattern across many days, not a promise about any single one. A gap that looks large and unlikely to fill can trade back to the prior close within the first few minutes of the very session that looked most likely to run away, and a small gap that "should" fill can hold open all day on the wrong news. Treat the size tiers as a genuine lean in the odds, not a rule for what one specific gap will do this morning.
