The objective of the game is to guide a frog to each of the empty homes at the top of the screen. The game starts with three frogs. Losing all frogs is game over. The player uses the 4-direction joystick to hop the frog once. Frogger is either single-player or two players alternating turns.

The frog starts at the bottom of the screen, which contains a horizontal road occupied by speeding vehicles such as race cars, dune buggies, trucks, and bulldozers. The player must guide the frog between opposing lanes of traffic to avoid becoming roadkill and losing a life. After crossing the road, a median strip separates the two major parts of the screen. The upper half consists of a river with logs, alligators, and turtles, all moving horizontally across the screen in opposite directions. By jumping on swiftly moving logs and the backs of alligators and turtles, the player can guide the frog to safety. The player must avoid snakes, otters, and the open mouths of alligators. A brightly colored female frog is sometimes on a log and may be carried for bonus points. The very top of the screen contains five "frog homes", and at least one is always open and available. These sometimes contain bonus insects or deadly alligators.

When all five frogs are in their homes, the game progresses to the next level with increased difficulty. After five levels, the difficulty briefly eases and yet again progressively increases after each level. The timer gives 30 seconds to guide each frog into one of the homes, and resets back to 60 ticks whenever a life is lost or a frog reaches home safely.