In this guide
The core calculationWhere subjectivity entersWhy “target” can be misleadingUse the calculator as a geometry toolThe core calculation
If a hypothetical range spans 80 to 100, its height is 20. Projecting that height upward from 100 gives 120. Projecting it downward from 80 gives 60. The arithmetic is deterministic once the three inputs are chosen.
Where subjectivity enters
The difficult part is usually not subtraction; it is deciding which high, low and breakout reference define the pattern. Two people can look at the same chart and choose different boundaries, so they can obtain different measured-move values while both performing the math correctly.
Why “target” can be misleading
Many charting resources call the projection a “price target”. That wording can sound predictive. PreBreakout instead labels it a measured-move formula result. The distinction is deliberate: a projected level says nothing about the chance that a future path will reach it.
Use the calculator as a geometry tool
Try several fictional ranges with the same width and different breakout levels. Then keep the breakout level fixed while changing range height. This makes it obvious which inputs drive the result.