Displacement–length ratio

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The displacement–length ratio (DLR or D/L ratio) is a calculation used to express how heavy a boat is relative to its waterline length. (Rousmaniere, 1999)

A DLR is calculated by dividing a boat's displacement in long tons (2,240 pounds) by the cube of one one-hundredth of the waterline length (in feet):

<math>\mathit{DLR} = \frac{\mathit{displacement}(\mathrm{lb}) ~/~ 2240} {(0.01 \times \mathit{LWL}(\mathrm{ft}))^3}.</math>

The DLR can be used to compare the relative mass of various boats no matter what their length. A DLR less than 200 is indicative of a racing boat, while a DLR greater than 300 or so is indicative of a heavy cruising boat.