The length of a frog's ability to hold its breath varies by species. Most frogs are able to spend a prolonged period of time underwater by breathing through their skin.
Tadpoles have gills that allow them to breathe underwater indefinitely. These gills are lost when the tadpole completes its metamorphosis into a frog.
Frogs have the ability to breathe through their skin using a process called cutaneous gas exchange, or cutaneous respiration, which allows them to spend lengthy periods of time underwater without returning to the surface for air. This is a frog's primary form of respiration. Frogs are also able to breathe through their lungs, allowing an alternative to cutaneous respiration if necessary.