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A blue whale swimming with a visual comparison of its heart🐋 Animal world

From the fact archive Friday, 4 September 2026

A blue whale has a gigantic heart!

The blue whale has the largest animal heart, which can weigh around 180 kilograms.

That powerful heart pumps blood through a body that can exceed 25 metres. Yet its heartbeat becomes very slow during deep dives.

Trusted source: NOAA Fisheries