Betta splendens is a species of freshwater fish in the genus Betta. Betta splendens are native to Thailand. They are a popular aquarium fish species. They are known for their interesting behavior, bright colors, and ability to breathe air.

In the wild, bettas live in rice paddies, canals, and small rivers.

Males are more colorful and usually have larger fins than the females. There are many color patterns and fin types of Betta splendens. Female bettas have a more pointy shape at their stomachs. Betta splendens can be up to 6.5 centimeters long.