How small is a newborn koala?
A newborn koala is roughly the size of a jellybean, weighing less than half a gram.
After a remarkably short 35-day pregnancy, the tiny joey emerges weighing less than one gram. Blind and hairless, it must crawl entirely on its own into its mother's pouch, where it will develop for another six months before emerging fully formed.
Nerd Mode
Koalas (Phascolarctos cinereus) have one of the shortest gestation periods among mammals, lasting only 33 to 35 days. When born, the joey measures roughly 2 centimeters long and weighs approximately 0.5 grams—about the same as a single paperclip or jellybean. At this stage, the joey is pink, hairless, and completely lacking developed eyes and ears.Despite being blind, the newborn possesses remarkably strong forelimbs and a keen sense of smell. These adaptations enable it to navigate the challenging journey from the birth canal to the mother's pouch without assistance. While the mother does not actively help, she may lick a path through her fur to ease the trek slightly. This climb represents a critical survival test for the tiny marsupial.Once inside the downward-facing pouch, the joey attaches to one of two teats. The teat swells inside the joey's mouth, creating a secure physical bond that prevents it from falling out. The joey remains in the pouch for approximately six months, gradually growing fur and opening its eyes. By the time it emerges, it has transformed from a jellybean-sized newborn into a fully formed miniature koala.
Verified Fact
FP-0002686 · Feb 17, 2026