What is the size of a watermelon seeds?

Watermelon seeds typically range in size from about 0.5 to 1 inch in length (1.3 to 2.5 cm) and about 0.3 to 0.5 inches (0.8 to 1.3 cm) in width. The size can vary depending on the specific variety of watermelon. Generally, they are oval-shaped and have a hard, glossy outer shell.