Methodology & filters
Gap = open / previous session close − 1. Common stocks and common-stock ADRs, any volume, without a Top 20 cap. Default ≥20%; presets ≥50%, ≥100% and custom inclusive ranges. Color represents opening gap.
HOD is the highest split-adjusted minute-bar high from 04:00–20:00 ET; early-close sessions use shortened hours. Ties use the first minute. Aggregates include provider-eligible trades, not every trade print.
The default view shows the last 20 completed trading days, newest first; monthly review is also available. Horizontal position shows HOD time; higher vertical position means a larger opening gap. Each date uses its own log(1 + gap% / 100) scale, from zero to its largest plotted gap plus 15%, rounded up to a readable limit. Rows have fixed heights and vertical padding. Heights are not directly comparable across dates; refer to each row’s scale or the exact values. Each dot represents one ticker at its true time and gap coordinates. Dots may overlap; they are never grouped or displaced. Hover, select or focus a dot for its exact time, gap, HOD and source timestamp.
Unfinished days, missing archives and no eligible minute bars are distinct. This tool is for historical review, not a live intraday scanner.
