According to The Exploratorium, many, but not all, frogs have webbed feet. The back feet of frogs that live around water are webbed. Both front and back toes of Costa Rican flying frogs have webbing that helps them sail between trees. Tree frogs have sticky pads instead of webbing.
All frogs have four toes on their front feet and five on their hind limbs. Aquatic frogs typically have long, strong back legs to propel themselves through the water. The shorter legs of land-dwellers are more useful for walking and climbing. An unusual type of foot is found on the spadefoot toad. Both back feet have spikes, and the frogs use them to dig underground burrows.