King Penguin
Aptenodytes patagonicus
The king penguin stands at 70 to 100 cm (28 to 39 in) tall and weighs from 9.3 to 18 kg (21 to 40 lb). Although female and male king penguins look alike, they can be separated by their calls. Males are also slightly larger than females. The mean body mass of adults from Marion Island was 12.4 kg (27 lb) for 70 males and 11.1 kg (24 lb) for 71 females. Another study from Marion Island found that the mean mass of 33 adults feeding chicks was 13.1 kg (29 lb). The king penguin is approximately 25% shorter and weighs around a third less than the emperor penguin.
ID text from Wikipedia, CC BY-SA 4.0

Little Penguin
Eudyptula minor
Like those of all penguins, the wings of Eudyptula species have developed into flippers used for swimming. Eudyptula species typically grow to between 30 and 33 cm (12 and 13 in) tall and on average weigh 1.5 kg (3.3 lb). The head and upper parts are blue in colour, with slate-grey ear coverts fading to white underneath, from the chin to the belly. Their flippers are blue in colour. The dark grey-black beak is 3–4 cm long, the irises pale silvery- or bluish-grey or hazel, and the feet pink above with black soles and webbing.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: King Penguin and Little Penguin.