What Defines a Tradeable Gap on a Scanner?
A gap is the difference between today's opening print area and yesterday's close. Scanners quantify it as percent gap up or down. Tradeable gaps combine meaningful percent—often three to fifteen percent for large caps, higher for small caps—with supporting volume and a identifiable catalyst. Without volume, gaps fade. Without catalyst, gaps lack follow-through narrative. Filter gap min to exclude noise and gap max to exclude likely halt-prone parabolic opens unless you specialize in that sub-style.
Separate scan presets for gap up long continuation and gap down short continuation—rules differ.
How Do You Scan for Gap-and-Go Versus Gap Fade?
Gap-and-go scans: gap up, pre-market volume above threshold, price holding above prior close pre-market, sector strength, float not microscopic. Entry triggers often break pre-market high after open with rising relative volume. Gap fade scans: gap up on weak catalyst or into daily resistance, lower pre-market volume trend, exhaustion candle patterns at open. Requires clear failure signal—lose VWAP or opening low—not anticipatory shorting. Run different scans; mixing rules produces contradictory alerts.
Tag each morning's gap leader by type before choosing strategy—breakaway, common, or exhaustion gap.
What Volume and Liquidity Filters Protect Gap Traders?
Minimum average daily volume—five hundred thousand to one million shares for many day traders. Pre-market dollar volume floor. Maximum spread proxy via price tier—avoid sub-three-dollar names if slippage hurts edge. Relative volume at open climbing, not collapsing. Dollar volume rank in top fifty of your universe. Gap scanners that ignore liquidity produce untradeable alerts on the hottest percent gainers with no shares available at quoted prices.
If pre-market volume is high but open volume dries up, downgrade from A-list to watch-only immediately.
How Should Stops and Targets Work on Gap Setups?
Continuation long: stop below opening low or VWAP reclaim failure; target prior day high extension or measured gap fill inverse. Fade short: stop above opening high or pre-market high; target partial gap fill or VWAP. Size smaller on open than mid-day—volatility is highest first fifteen minutes. Partial profit at one R reduces stress when gaps reverse quickly. Write rules before the bell; gap emotion punishes improvised risk.
Time stop—exit if no follow-through within fifteen to thirty minutes when trading opening gap momentum.
What Common Gap Scanner Mistakes Should You Avoid?
Chasing percent leader without shares at ask. Shorting gap strength without borrow check. Trading every gap scan hit instead of top two by volume. Ignoring daily chart overhead. Fading earnings gap winners on hope. Gap scanner strategies succeed when filters enforce liquidity and catalyst quality and execution waits for confirmation bar closes.
Journal gap type and outcome weekly—regime shifts which gap style pays for months at a time.