Definition
A diving board is a chart configuration in which price moves sideways along a long, flat shelf of support and then drops sharply once that shelf gives way. The name comes from the visual: a level platform that ends abruptly, after which price plunges into open space below.
The flat shelf represents a price level where demand has held steady for an extended period. When that demand finally fails, there is little structure beneath to slow the descent.
Why it matters
How it works
While the shelf holds, buyers reliably defend the same price, producing a flat band of support over many sessions. The longer this shelf persists, the more orders and expectations cluster around it. When sellers finally overwhelm that support, stop orders and forced selling can cascade, since the prior decline left a relative vacuum of buyers underneath.
Traders monitor a diving board by drawing the shelf as a clear support line. A decisive close below it, especially on heavy volume, signals that the dive may be underway, and the height of the prior structure can help estimate how far the drop might extend.