1. Emperor Penguin (`Aptenodytes forsteri`): The emperor penguin is the largest of all penguin species, with an average height of 45 to 47 inches (115 to 120 cm) and weighing up to 88 pounds (40 kg).
2. King Penguin (`Aptenodytes patagonicus`): The king penguin is the second-largest penguin species, with an average height of 32 to 39 inches (80 to 100 cm) and weighing up to 33 pounds (15 kg).
3. Gentoo Penguin (`Pygoscelis papua`): The gentoo penguin is the third-largest penguin species, with an average height of 28 to 35 inches (70 to 90 cm) and weighing up to 15 pounds (6.8 kg).
4. Magellanic Penguin (`Spheniscus magellanicus`): The Magellanic penguin is the fourth-largest penguin species, with an average height of 26 to 32 inches (65 to 80 cm) and weighing up to 13 pounds (5.9 kg).
5. Rockhopper Penguin (`Eudyptes chrysocome`): The rockhopper penguin is the fifth-largest penguin species, with an average height of 21 to 26 inches (53 to 65 cm) and weighing up to 11 pounds (5 kg).