The short answer is that millipedes do not have a fixed leg count. They are not all close to 1,000 legs, and the number varies by species and by age. Juveniles have fewer body segments and fewer legs than adults, then gain more as they grow.
Why millipede leg counts vary
Millipedes are many-segmented arthropods, and most body segments carry two pairs of legs once the animal has passed the earliest stages of development. As a millipede grows, it adds more segments, so the number of legs rises too. That means a small juvenile can look very different from a mature adult, even within the same species.
So when people ask how many legs a millipede has, the most accurate answer is that it depends on the species and the life stage. Some species have relatively few legs, while others have many more. A young individual will not have the same leg count as a fully grown one.
The name millipede means thousand feet, but that is a historical nickname rather than a literal count. If you want a broader overview of how these animals move, behave and should be handled, the Millipede Behaviour, Biology & Handling Guide is a useful next step.
How millipedes grow more legs
Millipedes do not emerge from the egg fully developed. They grow in stages, adding body segments as they mature, and those extra segments bring more legs with them. That is why juveniles usually have fewer legs than adults.
This growth pattern is also why leg count is not a quick way to judge a millipede at a glance. A smaller specimen may simply be younger rather than a different kind of animal. Size, segment number and leg count all change together as the millipede develops.
The millipede life cycle article explains this process in more detail: What Is the Millipede Life Cycle?
Why the topic matters
Knowing that millipedes change as they grow helps with identification and with setting the right expectations. They are not just long insects with lots of legs; they are a distinct group with their own body plan and development.
It also helps keepers understand what they are looking at when comparing species. A millipede with many visible legs is not necessarily more active or more advanced, and a species with fewer visible legs is not less interesting. Body shape, colour, surface activity and burrowing habits vary widely between species.
If you are still getting to grips with millipede biology, you may also find Are Millipedes Insects? helpful.
Useful context for keepers
Millipedes are closely associated with leaf litter, rotting wood and other decaying plant material. Their long, segmented bodies suit life in tight spaces, where they can move through soil and litter rather than across open ground.
That is why many species spend much of their time hidden or partially buried. A millipede that disappears into the substrate or remains out of sight for periods is often behaving normally.
If you are choosing a species, it helps to know that visible activity varies. Some millipedes are more surface-active than others, while some are naturally more secretive. The best choice is the one that suits the kind of animal you want to keep.
What to take away
Millipedes do not all have 1,000 legs, and they do not have a single fixed number either. Their leg count depends on species and age, with juveniles having fewer legs than adults and gaining more as they develop.
Once you understand that, the many-legged body plan makes more sense: it is part of an animal adapted for life in leaf litter, soil and decaying wood. If you want to go further, the Millipede Behaviour & Biology Guides collection covers the wider context behind millipede appearance, growth and care. You may also enjoy Why Do Millipedes Have So Many Legs?.