Just need the age of a frog when they begin to croak.how old are they? From birth or is it older
Answers:
They hatch from a mass of jelly-like eggs laid in the spring, and the tadpole grows for about three months. Then it sprouts tiny hind legs that get larger over the weeks of summer, while the tail is absorbed gradually. Front legs emerge from the gill openings, the tail gets down to nothing, and you have a young frog by the end of summer. By the following spring they make their characteristic mating calls, which is different (usually not a "croak") for each different species of frog. The Spring Peeper makes a high-pitched and very loud "peep-peep; peep-peep," and this is in the early spring, before other frogs are out yet. A Green Frog's call sounds like a plucked banjo string. A Wood Frog's call is a mid-range sort of noise, almost bird-like. A Bullfrog makes a sort of "moo-moo." So the answer to your question is "one year old, from the hatchling (tadpole) stage."
Almost from birth
3 to 4 months in bull frogs
The age for croaking is different with each species of frog. The best answer with out knowing the species you are asking about specifically would be they will begin to croak when they reach sexual maturity. In some bull frogs this is about 4-6 months in poison dart frogs this could be as much as 1 year. Hope this helps.