Totoro has grey fur and beige belly with grey arrows on his chest. He has pointy ears, long whiskers and large paws with long claws. His silhouette vaguely resembles that of an owl.
Big Totoro is thought to be King of the Forest. He often sleeps, and is the main Totoro, also being the logo for Studio Ghibli. He is voiced by Frank Welker in Disney version.
Medium Totoro is featured less so much. He is small and coloured a mixture of blue and grey with a white belly. Otherwise, he is physically the same as Big Totoro.
Small Totoro is the smallest. He is white and his features are a lot simpler, being limited to ears and eyes.