Frog: any member of a diverse group of short-bodied, tailless amphibians
There are over 5,000 species of known frogs, and scientists continue to discover new species
Frog species come in a variety of sizes and colors
Frogs are amphibians, which are cold-blooded vertebrates, meaning they have backbones, that don’t have scales
Amphibians live both on land and in water
What’s the difference between frogs and toads?
There isn’t a difference, the word “frog” includes both frogs and toads
While toads are frogs, toads tend to reference a frog that has particularly dry and warty skin
Frogs are more likely to live in or near water than toads
Size and Weight:
Frogs vary widely in size and weight depending on species
For example, the West African goliath frog can grow to 15 inches and weigh as much as 7 pounds
Meanwhile, the Cuban tree frog grows to only half an inch and weighs approximately 2 ounces
However, most species have large, protruding eyes so they can see in most directions without needing to turn their head
Most species are also great at hopping in any direction
Some frogs can jump over 20 times their own body length, which is similar to a human jumping 30 meters
Frogs come in a variety of colors, but they have two main color schemes
Both color schemes are used for different survival techniques
Meanwhile, the bright colors, like those of the poison frog, signal a warning sign to predators that their skin is toxic
Some South African frogs are so poisonous that you can die from them
Other frogs like the smooth-sided toad have glands behind the eyes that produce powerful toxins that kill anything that tries to eat them
As their skin, frogs and toads have a moist and permeable skin layer covered with mucous glands
Most species eat insects, spiders, worms, and slugs
However, some of the larger species are able to eat larger prey like mice, birds, and small reptiles
Frogs help keep a large part of the world’s insect population under control
Frogs thrive in a large number of environments from tropical forests to frozen tundras to deserts
Their skin requires freshwater, so most frogs live in aquatic and swampy habitats
There are a number of exceptions, including the waxy tree frog, which can be found in the arid region of Gran Chaco of South America
Waxy tree frogs produce a waxy substance that they rub all over their skin to prevent evaporation
Male frogs make calls to attract the females during the mating season
The female will choose a male whose call she likes, and the male will grab her as she releases her eggs in a mating hug called amplexus
Almost all frog species fertilize the eggs outside the female’s body
Amplexus can last hours, days, or in some species like the Andean toad, months
The mother will lay two to more than 50,000 eggs depending on the species
In many species, the male will guard the eggs
Although the father is more likely to perform this task, the mother also performs these tasks in some species
Certain species have different breeding rituals
For example, the marsupial frog keeps her eggs in a pouch like a kangaroo
Meanwhile, the Suriname toad of South America keeps her young embedded in the skin of her back
The gastric-brooding frog of Australia swallows her fertilized eggs until she releases them when they hatch
After about two to three weeks, depending on the species, the eggs hatch into tadpoles
Tadpoles, also known as pollywogs, have gills and a tail like a fish but a round head
Over the course of a few months, the tadpoles will gradually grow legs, absorb their tails, lose their gills, and turn into frogs that start breathing air and hopping
While most frogs metamorphose in a few months, some species take longer
For example, the mountain yellow-legged frog takes at least two seasons to morph, due to the cold temperatures and short summer season where it lives
Frogs are social creatures and live in groups called armies, colonies, or knots
Each species of frog has a unique call, which is used to attract a mate or to warn enemies
During the mating season, the male frogs croak loudly in a group
The life spans of frogs in the wild are widely unknown, but likely range from one day to 30 years
In captivity, frogs have been known to live more than 20 years
The largest threat to frog species is habitat loss related to human activity and human expansion
Humans have introduced nonnative species like trout and even other frogs to certain habitats that eat many of the native frogs
Pollutants from human activity often contaminate the rivers and ponds of frogs, killing local frog and tadpole populations
Another major threat to frog populations is the spread of a fungus called chytrid (Batrachochytrium dendrobatidis)
The disease led to the catastrophic decline or extinction of at least 200 species of frogs and other amphibians
The fungus lives in water, so frogs are easily infected
The fungus covers their thin skin so the frog can’t breathe or get water
Not only does the fungus affect the frog, but it also affects larvae and tadpoles, growing on their mouthparts and preventing them from eating
Over 500 species of frogs are listed as “Critically Endangered” The world is currently facing an amphibian extinction crisis
There are a number of conservation groups and government agencies working to protect amphibian species
National Wildlife Federation and Save the Frogs are among the various organizations working toward frog conservation
In response to the spread of the chytrid fungus, the Panama Amphibian Rescue and Conservation Project are working to save frogs through biosecurity consultation and education, providing disease testing to over 80 zoos nationwide
According to the San Diego Zoo Wildlife Alliance, 60 amphibian species in Central and South America have been rescued and are being maintained in safe survival-assurance colonies until a time when it is safe to return them to their habitat
Twelve of the most at-risk species have now reproduced in managed care, including the horned marsupial frog, crowned tree frog, and Limos harlequin frog
In the United States, the mountain yellow-legged frog (Rana muscosa) of Southern California is critically endangered, largely as a result of habitat loss, drought, pollution, introduced predators, and chytridiomycosis
The San Diego Zoo Wildlife Alliance is working to restore the ecosystem balance in its habitat of the San Jacinto Mountains through managed breeding and reintroduction efforts for the mountain yellow-legged frog
Since 2010, the zoo has successfully reintroduced zoo-bred mountain yellow-legged frog tadpoles into the wilderness
One of the most amazing things about frogs is that there are over 7,500 different kinds and more being discovered every month by scientists around the world
Since there are so many frogs species, their size and weight can greatly vary from one frog to anotherAs a general rule, the average weight of frogs is around 227 g (080 oz), but some frogs can reach 3 kg (72 lb) while other frogs are as light as 001 g (00003 oz)
A frog’s weight mostly depends on the species, but can also be influenced by availability of food, predation, and environmentThis table includes a variety of frog species and their average weight:Frog SpeciesAverage Length (cm)Average Weight (g)Paedophryne amauensis077001Mimic Poison Frog1-21-2Blue Poison Dart Frog2-48-10Golden Poison Frog2-58-10Gray Treefrog3-57-10Wood Frog3-87-12Pickerel Frog45-757-12Tomato Frog5-1040-225Northern Leopard Frog5-1222-25Red-eyed Tree Frog5-655-15African Dwarf Frog5-652-5Amazon Milk Frog6-104-5Common Frog9-1320-25American Bullfrog9-15175-500Australian Green Tree Frog10-115175-250Argentine Horned Frog (Pacman Frog)10-17225-500African Bullfrog20-25700-14Goliath Frog25-32 25-33Beelzebufo (extinct)425NAWhen it comes to frog size and weight, frogs vary profoundly depending notably on the species
Frogs also have to adapt to certain environmental conditions, forcing them to evolve to reach certain sizes
This is why some frogs tend to be gigantic in frog standards while other frogs are no bigger than a pennyWhat Influences Frog Weight?With over 7,500 known frogs, the species is the main factor that influence the weight a frog may attain
However, age, food availability, predation, temperature, humidity, time of year, and overall environment also influence how much a frog may weighHere is an explanation as to what factors influence frog weight:Species: This is the main factor that influences frog weight since genetics often dictate how heavy or light a frog will be depending on the species
Tree frogs are often much lighter than aquatic or terrestrial frogs because they climb trees and live on leaves and branchesAge: Age is also an important factor since frogs undergo profound metamorphic changes through their life cycle
Eggs, tadpoles, and froglets are generally lighter than adult frogsFood: Frogs that have abundant access to food will generally weigh more than frogs that have scarce access to foodTemperature: Temperature and humidity may play a role in a frogs weight as a study found that “the rate of weight loss was significantly higher at high temperatures than at low temperatures and increased logarithmically with temperature” (Jameson, 1966)Predation: If there are many predators around, it may be harder for frogs to survive and access food
Needing to escape predators takes up energy which can prevent a frog from gaining weight
Some frogs also need to grow large enough to survive among larger predators within their environmentEnvironment: A frog in a predator-free, food-abundant environment will tend to be larger than a frog that is constantly under pressure or stress within their environmentTime of year: Frogs are generally lighter after hibernation or estivation, and generally larger or heavier before hibernation or estivation as part of their preparation for this processThere were a few toads that roamed my yard when I was a kid and one of them was very skinny at the beginning of Summer, but had a very large stomach by the end of the Summer thanks to the abundant presence of bugs and the absence of predatorsSome frogs are so light that you can’t even feel a thing when you try to carry them
Meanwhile, other frogs species are so large they can eat mice, bats, and small mammalsWhich Species Of Frogs Is The Heaviest?Goliath Frogs are the heaviest known and alive frog species at 32 cm or 125 inches and weighing 33 kg or nearly 73 pounds
However, the extinct Beelzebufo is said to have reached 425 cm or nearly 17 inches long which would have made it much heavier than Goliath FrogsThe heaviest frog species is also the world’s largest frog
Goliath Frogs can be found in the equator area of West Africa and are the largest and heaviest frogs we have in the world todayHowever, there was a time when the Goliath Frog was not the biggest frog on the planet
Beelzebufo ampinga, or simply Beelzebufo, is a prehistoric species of frog that is said to have lived in Madagascar 70 million years agoIn a way, this is the dinosaur ancestor of the frogs we have today as they could reach lengths of 425 cm or nearly 17 inches long
There is no clear indication of how heavy Beelzebufo was, but it would have been much heavier than the Goliath Frog since it is largerWhich Species Of Frogs Is The Lightest?The world’s smallest known frog species is Paedophryne amanuensis with an average length of 077 cm and weight of 001 grams
This frog is so tiny that it is much smaller than a human fingernailThe size difference between the world’s biggest frog and the world’s smallest frog is so huge that the Goliath Frog is about 3,300 times heavier than the Paedophryne amanuensisPaedophryne amanuensis were recently discovered (Rittmeyer et al, 2012) in Papua New Guinea
A group of scientists was able to discover the frog species by tracing loud frog calls at night
This brought them to some leaf litter, which they carefully looked through until they saw plenty of tiny frogs hopping aroundThe reason why these frogs are so small can be tied to the fact that they like living in leaf litter while eating very small insects that also live in such places
Frogs that also live in leaf litter tend to be small, like the Spring Peeper which can be very difficult to spot in the wild as I demonstrate below:Do You Hear Crickets in Spring?
🙂 Subscribe to our YouTube channel for more!More About Frog SizesLearn more about different frogs species, their weight and size on our blog:How Big Can Frogs Get?Frog Profiles: More About The Size, Weight, And Features of Different Frog SpeciesFrog Anatomy: Everything You Need To KnowSourcesJameson, David L
“Rate of Weight Loss of Tree Frogs at Various Temperatures and Humidities” Ecology, vol
Austin, Ecological Guild Evolution and the Discovery of the World’s Smallest Vertebrate, January 11, 2012 https://doiorg/101371/journalpone0029797
And then there are the thousands of different species
But what kind of size does the average frog get; what is the range?
So, how big do frogs get?
Frogs can be anywhere from <1-32 cm in length (from snout to vent) and weigh anywhere between 05g-3/2 kg It depends entirely on the species Although, the average size for all frog species is around 6-12 cm in length and 10-75 grams in weight As you can see, it’s almost impossible to get an exact figure for either length or weight Because there are 4,810 known species of frog, and chances are, there is more out there And frogs (which can be found on all continents and geographical locations) vary Not just in relation to other frogs but to other amphibians and animals in general So, let us now take a closer look at the factors that influence the size of a frog before moving onto the average size of 18 of the most common species! Factors That Influence Frog SizeSpeciesSexDietThe Average Size Of 18 Different Frog SpeciesHow Long Do Frogs Take To Grow To Full Size?What Is The Smallest Frog In The World?What Is The Largest Species Of Frog?FinallyRelated Questions Factors That Influence Frog Size Frogs can vary dramatically in terms of size and weight, and there are generally three different reasons for this: species, sex, and diet Species The size potential of a frog is largely determined by genetics More specifically, the species It is within each species that you get a typical pattern developing in results to their size And frogs within a species will not gravitate much outside of this range But for the most part, a frog of one particular species will grow to a specific, almost anticipated size The sex of a frog has a lot to do with its final size And for frogs, it’s not as simple to say that males are bigger than females, or vice versa In some species, males are larger In other species, females are larger Take the African Bullfrog, for instance; males can reach almost double the size of the females But in South American Horned Frogs (sometimes referred to as Argentine American Horned Frogs or Pacman frogs), females grow significantly larger than males The diet of a frog largely determines the size a frog can become within reason It’s only logical that a frog with access to more food and more energy will grow bigger and heavier And due to the way frogs consume their foods, whole, it’s a bit of a cycle here Larger species of frogs can eat bigger prey, even as large mice, which in turn leads to them putting on more weight And frogs can put on excess weight too if they eat too much for their given need That’s right, obesity in amphibians is a thing The Average Size Of 18 Different Frog Species Below we will take a look at the average size and weight of 18 of the most common frog species Some of these are kept as pets, whereas others are the more notable wild species Be sure to remember that these numbers are averages and frogs can always fall outside of this range
I have ordered the data in terms of smallest to the largest:
Frog SpeciesAverage Size(Snout to Vent – Length)(In Centimeters)Average Weight(In Grams/Kilograms)Mimic Poison Frog1-2 cm1-2 gBlue Poison Dart Frog2-4 cm8-10 gGolden Poison Frog2-5 cm8-10 gGray Treefrog3-5 cm7-10 gWood Frog3-8 cm7-12 gPickerel Frog45-75 cm7-12 gTomato Frog5-10 cm40-225 gNorthern Leopard Frog5-12 cm22-25 gRed-eyed Tree Frog5-65 cm5-15 gAfrican Dwarf Frog5-65 cm2-5 gAmazon Milk Frog6-10 cm4-5 gCommon frog9-13 cm20-25 gAmerican Bullfrog9-15 cm175-500 gAustralian Green Tree Frog10-115 cm175-250 gGoliath frog25-32cm 25-33 kgArgentine Horned Frog (Pacman Frog)10-17 cm225-500 gPixie Frog12-25 cm900-18 kgAfrican Bullfrog20-25 cm700-14 kgGoliath Frog25-32cm 25-33 kg
As you can see, there is quite a variety in size!
Equally, just because may be larger in terms of their length, does not necessarily mean they will carry more weight
The truth is, frogs come in a range of different body types
How Long Do Frogs Take To Grow To Full Size?
How long a frog takes to grow to its full size will depend on the species
Smaller frogs generally reach their full adult maturity much quicker than larger species; there is less to grow!
Each species of frog will go through its own cycle of development
This is known as ‘metamorphosis’ Or, in other words, the progression from one life stage to the next
But it generally looks something like this:
Egg,Tadpole,Froglet,Young FrogAdult Frog
And for a smaller frog, such as the common frog, they can reach their full size in as little as 12-14 weeks
But for larger frogs, it can take as long as 6-12 months for them to reach their final size
Almost every frog species will do their growing early on in life, but there are reported cases of frogs continuing to add weight and mass as they continue to age
Pixie frogs are a prime example, for instance
An underfed frog will not develop the same amount of mass as an overfed frog of the same species
What Is The Smallest Frog In The World?
The smallest known and currently discovered frog in the world measures 7 millimeters in length
The frog species, the scientific name Paedophryne amauensis, was discovered in Papua New Guinea by a US-based research team in 2012
More recently, another species of tiny frog was discovered in Madagascar
Of course, these are only the frogs discovered
What Is The Largest Species Of Frog?
The largest species of frog is the Goliath frog
Appropriately named, this species grows up to 125 inches (32 centimeters) in length and can weigh up to 72 pounds (33 kilograms) when fully grown
Stated differently, the size of this frog compares in the following way:
Bigger than a Guinea PigBigger than a RabbitThe same size as some cats!
Frogs come in all shapes and sizes
So much so that some frogs dwarf in comparison to others
Quite literally in the case of an African Dwarf Frog and a Mimic Poison frog!
And then there are the African Bullfrogs and Goliath
With all this in mind, it’s essential you consider the size of each species at their full-grown size
Besides, the size of a frog will have big implications for their care and needs
So even if all frogs start out as tadpoles of a similar size, where they end up, is… ultimately entirely varied!
How Big Do Pacman Frogs Get?
Pacman frogs typically reach between 10-17 cm in length (snout to vent) and 225-500 grams at full adult size
They are considered medium-sized
How Big Do African Dwarf Frogs Get?
African Dwarf frogs typically reach between 5-65 cm in length (snout to vent) and 2-5 grams at full adult size
Bullfrogs can vary in size depending on whether it is the American or African species
The American Bullfrog will typically reach between 9-15 cm in length (snout to vent) and 175-500 grams at full adult size whereas the African Bullfrog will typically reach between 20-25 cm in length (snout to vent) and 700-14 kilograms at full adult size
Treefrogs frogs typically reach between 3-5 cm in length (snout to vent) and 7-10 grams at full adult size
They are considered small-sized
They are considered small-sized