Iguana vs Lizard
Verdict: An iguana is a lizard, so the real question is whether you have a green iguana or some other lizard. A large dewlap, a row of back spines, and a body up to 6 feet long point to an iguana.
Iguanas are lizards, in the same way a collie is a dog. They belong to the family Iguanidae in the order Squamata, which also holds snakes and about 50 families including geckos, skinks, and monitors. So this page asks what makes a green iguana different from other lizards.
Most people searching this are looking at a big green lizard in Florida or a pet shop. The clues that matter are size, the dewlap under the chin, the spiny crest down the back, and what it eats. Young iguanas are smaller, so check several clues together.
Iguana vs Lizard side by side
| Trait | Green iguana | Other lizards |
|---|---|---|
| Classification | Family Iguanidae, order Squamata | Many families in Squamata, such as geckos, skinks, and monitors |
| Adult length | About 6 ft (2 m) for mature adults, males over 6 ft | Most other lizards are smaller than a mature iguana |
| Weight | Typically 4 to 6 kg (about 9 to 13 lb) | Depends on the species, from tiny geckos to large monitors |
| Throat | Huge dewlap, most prominent in males | Native Florida lizards lack an iguana-style dewlap |
| Back | Row of spines (dorsal crest) down the back | Native Florida lizards lack this spiny crest |
| Adult diet | Strict vegetarian: leafy greens, ripe fruit, flowers | Often not strictly vegetarian |
| Where it lives | Mostly arboreal, often in canopy near water | Varies by species, many live low or on the ground |
| Color | Bright green when young, grayish green as an adult | Many colors, often brown or tan |
| Lifespan | About 8 years in the wild, over 20 in captivity | Varies widely by species |
Last verified October 2026. Typical values; individual animals, products and local prices vary.
When you are looking at which
Green iguana
- The lizard is huge, with a long whip-like tail, and its body is well over a foot long.
- A large flap of skin hangs under the chin and throat.
- A row of spines runs down its back from neck to tail.
- It is up in a tree canopy beside a canal, eating leaves or flowers.
Other lizards
- The lizard is small, fits in your hand, and has no hanging throat flap.
- There is no spiny crest down the back.
- It is darting along a wall, rock, or ground and may eat insects.
- It looks brown or tan and is not strongly green.
How this works
The quiz adds up cues for a green iguana versus a typical other lizard. Dewlap, back spines, and adult size are the strongest because they separate iguanas from most small native species. Answer only what you could see, and choose I can't tell for the rest so one unclear detail does not decide the result.
It treats green iguanas as the iguana example. Other iguanas, such as desert or rhinoceros iguanas, and large lizards like monitors are not scored, so a big lizard without a dewlap may be something else. A tie means your answers were split, and a close look at the throat and back usually settles it.
Where these numbers come from
The figures and defaults on this page are based on:
- Florida Fish and Wildlife Conservation Commission: Green Iguana, Size, dewlap, spines, vegetarian diet, and Florida habitat. (checked October 2026)
- Animal Diversity Web: Iguana iguana (green iguana), Classification, weight, diet, lifespan, and eggs. (checked October 2026)
- Animal Diversity Web: Squamata, Squamata includes lizards, snakes, and about 50 families. (checked October 2026)
Field-identification guide. Do not release pet iguanas, and check local rules on non-native reptiles.
Frequently asked questions
Is an iguana a lizard?
Yes. Iguanas are lizards in the family Iguanidae within the order Squamata. That order also includes snakes, geckos, skinks, and monitors.
How big does a green iguana get?
Mature green iguanas are about 2 meters (about 6 feet) long. Most adults weigh 4 to 6 kilograms, and some well-fed South American animals reach 8 kilograms.
What do iguanas eat compared with other lizards?
Adult green iguanas are strict vegetarians that eat leafy greens, fruit, and flowers. Young iguanas sometimes eat insects, and many other lizards eat more animal food.
Are iguanas native to Florida?
No. Green iguanas live in Central and South America. Florida wildlife officials list them as a non-native species found in urban and suburban areas of south Florida.
Explore the whole Calcs family here.
Not happy with the answer or how it works? Let us know.
Have a suggestion for a comparison you don't see here? Let us know.
All VersusCalcs tools
Animals
American Crow vs Raven Anaconda vs Python Antelope vs Deer Ape vs Monkey Badger vs Wolverine Bald Eagle vs Golden Eagle Beagle vs Basset Hound Bernese Mountain Dog vs Saint Bernard Bison vs Yak Black Bear vs Grizzly Black Widow vs False Widow Bobcat vs Lynx Border Collie vs Australian Shepherd Boxer vs Bulldog Buffalo vs American Bison Butterfly vs Moth Camel vs Dromedary Carpenter Bee vs Bumble Bee Cavalier vs Cocker Spaniel Centipede vs Millipede Cheetah vs Jaguar Chihuahua vs Pomeranian Chimpanzee vs Gorilla Cicada vs Locust Copperhead vs Corn Snake Copperhead vs Water Snake Corgi vs Shiba Inu Cottonmouth vs Water Snake Coyote vs Fox Crocodile vs Alligator Crow vs Blackbird Deer vs Elk Doberman vs Rottweiler Dolphin vs Porpoise Donkey vs Mule Dragonfly vs Damselfly Duck vs Goose Eagle vs Hawk Elk vs Moose Flea vs Tick Fox vs Wolf Frog vs Toad Garter Snake vs Ribbon Snake Goat vs Sheep Goose vs Swan Gorilla vs Orangutan Grasshopper vs Locust Great Dane vs Mastiff Grizzly vs Brown Bear Groundhog vs Woodchuck Hamster vs Gerbil Hare vs Jackrabbit Hawk vs Falcon Heron vs Crane Heron vs Egret Honey Bee vs Bumble Bee Hornet vs Wasp Hornet vs Yellow Jacket Husky vs Malamute Iguana vs Lizard Jackal vs Hyena King Snake vs Coral Snake Labrador vs German Shepherd Leopard vs Jaguar Lion vs Leopard Lion vs Tiger Lizard vs Salamander Llama vs Alpaca Maltese vs Bichon Frise Manatee vs Dugong Mink vs Otter Monkey vs Lemur Mosquito vs Gnat Mouse vs Rat Orca vs Killer Whale Osprey vs Eagle Otter vs Beaver Owl vs Hawk Paper Wasp vs Mud Dauber Pigeon vs Dove Pitbull vs Rottweiler Poodle vs Labradoodle Praying Mantis vs Stick Bug Python vs Boa Rabbit vs Hare Reindeer vs Caribou Salamander vs Newt Shark vs Dolphin Spider vs Scorpion Squirrel vs Chipmunk Starling vs Blackbird Stingray vs Skate Stork vs Crane Tick vs Bed Bug Tiger vs Jaguar Tortoise vs Terrapin Turtle vs Tortoise Vole vs Mouse Vulture vs Buzzard Walrus vs Seal Wasp vs Bumble Bee Water Buffalo vs Bison Weasel vs Ferret Wolf vs Coyote Yellow Jacket vs WaspAuto & Tools
5W30 vs 5W20 AWD vs 4WD All-Season vs All-Weather Tires Brushless vs Brushed Drill EV vs Hybrid Gas vs Diesel Pickup Truck Impact Driver vs Impact Drill Premium vs Regular Gas TIG vs MIG WeldingHome
Brass vs Bronze Concrete vs Asphalt Driveway Cotton vs Polyester Gas vs Electric Dryer Granite vs Marble Hardwood Floors vs Carpet Hardwood vs Engineered Flooring Linen vs Cotton Mini-Split vs Central Air Nylon vs Polyester Oak vs Maple PVC vs CPVC Pine vs Cedar Portable vs Window Air Conditioner Quartz vs Granite Countertops Shingles Roof vs Metal Roof Silk vs Satin Spray Foam vs Fiberglass Insulation Stainless Steel vs Aluminum Tank vs Tankless Water Heater Vinyl vs Laminate Flooring Wool vs CashmereKitchen
Air Fryer vs Convection Oven Blender vs Food Processor Cast Iron vs Stainless Steel Catfish vs Bullhead Clam vs Oyster Gas vs Electric Stove Instant Pot vs Crock Pot Lobster vs Crawfish Octopus vs Squid Salmon vs Trout Shrimp vs Prawn Toaster Oven vs ToasterYard, Pool & Garden
Cedar vs Juniper Centipede Grass vs St Augustine Chlorine Pool vs Salt Water Composite vs Wood Decking Crabgrass vs Nutsedge Determinate vs Indeterminate Tomatoes Maple vs Sycamore Mulch vs Rock Landscaping Pellet Grill vs Gas Grill Perennial vs Annual Pine vs Spruce Riding Mower vs Zero Turn Sod vs Seed Spruce vs Fir St Augustine vs Bermuda GrassTime Zones
AKST vs AKDT AKST vs PST BST vs GMT CST vs CDT CST vs MST CST vs PST Central vs Mountain Time Central vs Pacific Time EST vs CST EST vs EDT EST vs MST EST vs PST Eastern vs Central Time Eastern vs Mountain Time Eastern vs Pacific Time HST vs PST MST vs MDT MST vs PST Mountain vs Pacific Time PST vs PDT UTC vs GMTLanguage
Affect vs EffectNo tools match your search.