Gap workbench · the basics

What is a gap?

A gap is the difference between yesterday’s closing price and today’s opening price.

“A hole in the chart.”
Sami Abusaad
Yesterday4:00 p.m. ETNYSE regular-market close
Today9:30 a.m. ETNYSE regular-market open
What gaps do

Gaps compress time.

Sami’s example5 days → 30 minutes or lessA multi-day move compressed into a short window.
The ideaMore movement in less time.Sami’s summary of the opportunity.
His view#1 profit centerSami describes gaps as his leading profit center.
Magnetic qualities

Why gaps draw a trader’s attention

01 · Emotional shock

Sami says a big move can shock traders. He gives losses of $1,000, $5,000 or $20,000 as examples of what can leave them feeling trapped and making mistakes. He says, “We capitalize.”

02 · Focus

Gaps can help narrow the watchlist to stocks with a catalyst and potential volatility. They don’t guarantee follow-through; sideways stocks may offer little for day trading.

03 · Versatility
  • Day tradingIntraday setups
  • Swing tradingSetups held across sessions
  • SpecializeSome traders focus on gaps as their main setup
Different approaches, not promises of a particular result.
Read the full range

An opening gap does not always leave a void.

Compare yesterday’s high and low with the gap session’s full range.

01 · Void

The ranges stay apart.

Gap up in both

Today’s low stays above yesterday’s high. The space between them is the void.

Daily IllustrativeGap dayO 19.78H 21.61L 19.68C 21.43
18.0019.0020.0021.00D0D-1D-18D0
Shaded band: voidReconstructed daily candles

D0 = gap day. D-1 is the previous session; D+1 is the next.

Chart guide

Each candle represents one trading session, not a calendar day. Hover to inspect, tap to pin. Use arrow keys to inspect and Esc to clear.

Yesterday’s high18.35
Today’s low19.68
Void18.35 to 19.68
02 · Overlap

The ranges share prices.

Gap up in both

Today opens higher, then trades back into yesterday’s range. There is no full void.

Daily IllustrativeGap dayO 53.30H 56.10L 48.20C 50.50
304050D0D-1D-18D0
Shaded band: shared rangeReconstructed daily candles

D0 = gap day. D-1 is the previous session; D+1 is the next.

Chart guide

Each candle represents one trading session, not a calendar day. Hover to inspect, tap to pin. Use arrow keys to inspect and Esc to clear.

Yesterday’s high50.10
Today’s low48.20
Shared range48.20 to 50.10

Geometry, not trade quality. A void or overlap does not classify a gap as Pro or novice.

Compare Pro and novice gaps
Reconstructed daily examples, not historical OHLC. Regular-session ranges only.D-1: yesterday. D0: gap day. Hover to compare, tap to pin. Arrow keys inspect, Esc clears.
Bottom line

Use gaps to focus the search, not predict the outcome.

A gap can put a stock on the watchlist by drawing attention to a catalyst and potential volatility. That focus can save screening time, even in a quiet market. A gap is a starting filter, not a guarantee of follow-through or a tradable setup.

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