What’s the Difference Between Centipedes and Millipedes?​

When it comes to legs, centipedes and millipedes are nature’s overachievers. And although the two types of insects have their legginess in common, they have plenty of features and characteristics that easily set them apart. One’s a slow decomposer while the other is a faster-moving predator. Below, we crawl into the key differences between centipedes and millipedes so you’ll never confuse the two again.

What Are the Differences Between Centipedes and Millipedes?

Though sometimes similar in color and size, centipedes have fewer legs than millipedes and tend to be bigger and flatter. They also feed on other insects and small arthropods, whereas millipedes have a diet consisting of decaying organic matter, such as dead leaves, scraps, and yard waste. We’ve outlined more differences between the two types of insects below.

Centipedes vs. Millipedes: Differences in Appearance

At first glance, it can be easy to mistake a centipede for a millipede, and vice versa. But if you take a closer look, you’ll see that the two bugs each have differences in their size, color, shape, and number of legs. Below, we break down the looks of our many-legged friends (or, in some cases, foes). 

Size

Most centipedes range from about 1 to 6 inches long, while millipedes range from 0.5 to 4 inches long. Some species of both insects, such as the Amazonian giant centipede and the giant African millipede, can grow up to 12 to 16 inches long. 

Color

Most millipedes are gray, black, or brown with a more muted tone. Their exterior has a more matte appearance, as opposed to centipedes’ shiny, slick bodies. Centipedes have a more yellowish tone, but can also have a reddish brown coloring. 

Shape

Centipedes have a longer, flatter body type, which can help distinguish them from the smaller, more round and cylindrical shape of a millipede. 

Number of Legs

In general, centipedes have 30 to 100 legs. Millipedes, on the other hand, can have anywhere from 100 to 400 legs—some with closer to 700. The legs of centipedes stick out to the sides, which helps them move quickly, while the legs of millipedes slant downward, causing them to move at a much slower pace.

Feeding Differences

Centipedes and millipedes feast on opposite types of food; centipedes are carnivores while millipedes are mostly detritivores. As carnivores, centipedes tend to kill their prey by injecting them with venom. Millipedes, on the other hand, don’t have to kill their food as they feed on already decaying organic matter or eat the roots and seeds of seedling plants. 

Centipedes can bite small prey by using the venom in the legs of their first segment, but their venom is not harmful or poisonous to humans. And although they aren’t able to sting, millipedes can release a secretion as a method of protection from their predators. 

Habitat Differences 

Both centipedes and millipedes can thrive in moist, damp environments, and centipedes can also survive in dry habitats. Millipedes, however, rely on decaying organic matter for food, so they are less likely to survive in dry areas or deserts. Centipedes can be commonly found under rocks, leaves, or logs, while millipedes can be found in areas with heavy vegetation, such as gardens or forests. 

Lifecycle Differences

Although they share a lot of legs, the lifecycles of centipedes and millipedes are surprisingly different. Centipedes grow quickly and live shorter lives, usually around 1 to 6 years. They also tend to lay fewer eggs, and their young hatch with fewer legs. Millipedes, on the other hand, play the long game. They develop slowly, often taking years to reach adulthood, and can live 7 to 10 years or more. While both creatures molt to add legs as they grow, millipedes tend to lay more eggs and spend more time underground during their early stages.

Illness & Disease Differences 

Neither centipedes nor millipedes pose a risk to humans; however, centipedes can bite and cause pain, swelling, redness, and allergic reactions on occasion. Although millipedes can’t bite or sting, the secretion they release can lead to skin discoloration, itching, or a mild burn on the skin. If you encounter either insect, rest assured, they will not spread illness or disease if you come in contact with them. 

Prevention Differences

If you start to spot centipedes and millipedes lingering inside or outside your home, there are prevention methods you can put in place for both insects. Centipede prevention focuses on pest control, while millipede prevention is centered around moisture and habitat management. 

Centipede Prevention

The best way to eliminate centipedes is to remove their food source, which consists of other insects. You can keep these critters out of your home by sealing cracks, removing excess moisture, and clearing clutter that can entice insects to set up shop indoors. You can also look into hiring your local pest control specialist to inspect your home and come up with a tailored treatment plan. 

Millipede Prevention

Since millipedes feast on decaying organic matter, your best bet at preventing an infestation is to manage outdoor moisture and organic debris around your home’s exterior. This means removing leaf piles, wood piles, and mulch near your foundation.