What's the Difference?: Millipedes vs. Centipedes

Updated: Sep 3, 2019

What’s that bug in the dirt with all those legs? It’s probably a millipede or centipede. But how do you tell the difference?

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Millipedes and centipedes are often confused with one another, but they are different creatures. Their names are based on their many legs, but they’re misleading. Millipede means “thousand feet.” Centipede means “hundred feet.” But millipedes don’t have 1,000 feet, and most centipedes don’t have 100 feet.


Both have a lot of legs, but not as many as their names suggest. Most millipedes have less than 100 legs. A few kinds of centipedes have 100 legs, but most have far fewer.


We think of centipedes and millipedes as bugs, but they are not insects. They are actually arthropods, the same group of animals lobsters and crayfish belong to.


So we know millipedes and centipedes are similar, but how can you tell the difference between them? One way is their legs.


Centipedes have one pair of legs on every body segment. Millipedes have two pairs of legs on every body segment. Their legs also sit differently on their bodies. A centipede’s legs point away from its body. A millipede’s legs point at the ground. And centipedes usually have longer legs than millipedes.


You can also tell the difference by their behavior. Centipedes will run away when disturbed, such as when a log they are under is overturned. A millipede won’t run away. Instead, it rolls into a ball and stays still.


You can’t tell by looking at them, but centipedes and millipedes have different diets. Centipedes hunt for smaller arthropods to eat. Millipedes eat decaying plants.


Both millipedes and centipedes live everywhere in the world except Antarctica. Millipedes usually live in moist or damp places. Centipedes can live in almost every kind of habitat, even the desert.


Most millipedes and centipedes are small, but not all are. The biggest centipedes in the world can be more than 1 foot long! The biggest millipedes can be more than 10 inches.


If you see a millipede or centipede, don’t pick it up. Centipedes bite, which can feel like a bee sting. Millipedes don’t bite, but they leave a fluid on your hands that smells bad and might make your skin itch or burn.