Depending on the volume of water and force of colliding waters, whirlpools can appear in different sizes. Some whirlpools form and disappear over a short period of time, while some water systems keep whirlpools for centuries, according to the Niagra Parks website.

The duration of a whirlpool depends entirely on its cause: tidal whirlpools are cyclical and temporary, while permanent ocean eddies can last for months. Famous tidal whirlpools, such as the Moskstraumen in Norway or the Old Sow in Maine, "last" for the duration of the peak tidal flow—usually about 20 to 60 minutes—twice a day. Once the tide turns and the water reaches "slack," the vortex disappears. In contrast, large-scale oceanic whirlpools, known as mesoscale eddies, are formed by major currents like the Gulf Stream. In 2026, satellite tracking shows these massive swirling bodies of water can persist for 3 to 12 months as they drift across the ocean, transporting heat and nutrients across thousands of miles. On a much smaller and more dangerous scale, "man-made" whirlpools caused by dam spillways or collapsing underwater caves (like the 1980 Lake Peigneur disaster) last only as long as the drainage remains open. Thus, while the "scary" whirlpools of myth are usually brief, daily occurrences tied to the moon, the "real" whirlpools of the deep sea are semi-permanent features of the Earth's climate system.