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Komodo Dragon (Varanus komodoensis) Fact Sheet: Physical Characteristics

Komodo Dragon (Varanus komodoensis)

Physical Characteristics

Body measurements

Attribute Males Females
Weight up to 136 kg (300 lb) up to 70 kg (154 lb)
Length 3 m (10 ft) 2 - 2.5 m (6.6 - 8 ft)

General Appearance

Body size

  • Largest living lizard
  • Juveniles slender and agile
  • Adults more robust, with flatter bodies and proportionately shorter tails (compared to juveniles)
  • Males larger than females
  • Long neck for viewing surroundings (e.g., in tall grass)
    • Can raise head up to 40 cm (1 ft) above the ground
    • When lowered, head approximately 20 cm (0.7 ft) above ground


  • Toes have sharp, recurved claws
  • Lightweight skull (Fry et al. 2015)
    • Weak bite force in proportion to body mass
      • Strong pulling force allows them to de-flesh with high success (D'Amore et al. 2011)
  • Teeth specialized for catching and holding prey, as well as tearing/removing teeth
    • Serrated, laterally compressed , and curved backward
    • Sharp tip and broad base
    • Longest teeth are approximately 2 cm (0.8 in)
    • Use of a bite and slice strategy that creates a severe wound (Fry et al. 2015)
    • Komodo has 4-5 replacement teeth at each position
      • Many varanids have 1-2 replacement teeth
  • Venom produced by toxin-secreting glands of monitor lizards (Fry et al. 2006; Fry et al. 2009)
    • Facilitates blood loss after bite by causing persistent bleeding, leading to hypotension, of prey (Dobson et al. 2019)
    • Toxin of the lace monitor (Varanus varius) affects blood pressure and clotting ability of its prey
  • Short intestine
    • Carnivore diets (those high in proteins and lipids) don't require a great deal of digestive processing
  • Skin
    • Covered by osteoderms
      • Often compared to chain mail
    • Shedding occurs in patches
      • Begins in September
      • Lasts about 6 months each year
  • Tongue long and narrow, with a deep fork at its tip
    • Retracts into sheath inside the mouth; does not move freely
    • Partially supported by a complex structure of bone and cartilage called the hyoid apparatus
    • Used for locating prey and in social interactions
      • Not used to manipulate food, as in some other lizards


  • Most adults uniformly gray or clay-colored
    • Brighter, speckled skin until reach 4 years of age
      • Komodos of Flores retain brighter coloration
  • Little sexual dimorphism
    • Flanks of adult females more red than males
    • Yellowish-green nose spots more common in males
  • Light yellow tongue is species specific:
    • V. salvator has a blue tongue
    • V. dumerili and V. grayi have pink tongues

Other Physical and Physiological Characteristics


  • Sense of smell important in food detection
    • Komodo dragons can detect the scent of carrion from as far as 11 km (6.8 mi)
    • Decomposition releases volatile oils that Komodo dragons can detect
  • A pair of Jacobson's organs opens into the roof of the mouth
    • Scent particles collected by forked tongue and delivered to these sense organs
  • Each external nostril leads to a multi-chambered nasal capsule
    • One of the chambers functions to excrete excess sodium 


  • Keen eyesight
  • Eyes placed laterally
  • Covered by 2 different eyelids
    • Upper lid has little mobility
    • Lower lid contains a cartilaginous plate that slides over surface of the eye


  • Ear is important for maintaining balance, as well as sound reception
  • Behavior more scent than sound oriented


  • Varanid lungs larger than those of most reptiles
  • Take in relatively large amounts of oxygen and their physiology produces a more efficient system of air circulation
  • Breathing rate is regular and low
  • Varanids can voluntarily hold their breath for long periods


  • Varanids have a more complex heart structure and blood chemistry than other lizards
    • Allows them to achieve intense activity without becoming exhausted

Water/salt balance

  • Water makes up 70% of a lizard's body weight (10% more than in humans)
  • Varanid skin is covered with scales and contains no sweat glands
  • Excess sodium removed by special salt-secreting glands in the nasal capsules

No More Scrapes or Scratches

komodo dragon skin

The chain mail-like scales covering a Komodo dragon's body protect its skin.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Page Citations

Auffenberg (1981)
Ciofi (2004)
D'Amore et al. (2011)
De Lisle (1996)
Dobson et al. (2019)
King & Green (1993)
Fry et al. (2006)
Fry et al. (2009)
Fry et al. (2015)

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