Centipede vs. Millipede: Differentiating Between Many-legged Insects

Centipedes have a flatter body with segments that each bear one pair of legs. Their legs extend out from the body and give them a speed advantage, especially useful for capturing small creatures and avoiding predators.

Most centipedes range from yellowish to dark brown, and they look sleek and fast — makes sense, given the small insects that comprise their diet.

Millipedes, on the other hand, have a more cylindrical body, with each segment typically bearing two pairs of legs. Their segments are more compact and positioned for burrowing through decaying organic matter. Most millipedes are dark brown, slow-moving, and often curl into a spiral when threatened.

Centipedes feature one pair of legs per body segment, while millipedes generally have two pairs. That means a millipede looks denser and has many more legs moving in a wave-like motion.

Some species of centipedes have over 300 legs spanning their entire body, but due to their leg-per-segment structure, but they always have an odd number of leg pairs.

Millipedes can also have hundreds of legs, but in pairs per segment, often moving rhythmically as they navigate through soil or leaf litter.

The diet of centipedes is carnivorous. These carnivores actively hunt insects, spiders, silverfish, and even small cockroaches. Using venomous fangs, they kill prey and help with pest control indoors.

Millipedes are primarily detritivores, feeding on decaying plant material, microbial decomposition, and living plants only when decaying. By feeding on this matter, they enhance soil nutrient cycles and contribute to healthy ecosystems.

Common house centipedes are often seen indoors, especially in bathrooms and basements. They prefer humid environments and can be found under rocks, mulch, or debris when outside.

Millipedes thrive in moist habitats rich in organic matter. You might find them in gardens, compost piles, or under logs. During heavy rain or when the weather cools, they may enter homes in search of shelter.

When threatened, centipedes may bite. Their venom isn’t lethal to humans, but it can feel like a bee sting. They use speed and hiding to avoid predators.

Millipedes, lacking venom, roll into tight coils. Some species can emit irritating chemicals when disturbed, a defense that may ward off predators including pets or small children.

Centipedes lay eggs in soil or leaf litter — and, in many species, their larvae hatch with fewer segments, gaining more as they molt.

Millipedes lay clusters of eggs underground. Their juveniles gradually develop new segments and pairs of legs as they mature.

Centipedes and millipedes both serve vital purposes. Centipedes help manage populations of other insects and pests. Millipedes break down decaying organic material, supporting microbial ecosystems and soil structure.

We created this article in conjunction with AI technology, then made sure it was fact-checked and edited by a HowStuffWorks editor.