Hedgehog Life Stages & Age Calculator

Estimates only. There is no veterinary standard for hedgehog years to human years, and every hedgehog grows and ages a little differently. For a pet's health, see an exotic-animal vet; for a wild hoglet, call a hedgehog rescue.

Hedgehog life cycle diagram

The hedgehog life cycle has four stages: hoglet, juvenile, adult and senior. The calculator highlights your hedgehog's stage on this diagram. Pet African pygmy hedgehogs and wild European hedgehogs pass through the same stages, but wild ones mature later and stay juveniles through their first winter.

Hedgehog life stages at a glance

These are the hedgehog life stages the calculator uses, with ages for both kinds of hedgehog. The stages of a hedgehog's life are the same for both; only the timing differs.

The life cycle of a hedgehog is short and fast at the start. A pet African pygmy hedgehog goes from a 10–18 g newborn to a sexually mature juvenile in just 2–3 months (Merck). A wild European hoglet is independent at 4–6 weeks but usually doesn't breed until the spring after its first hibernation.

Hoglets: newborn to weaning

A baby hedgehog is called a hoglet. Pet African pygmy hedgehogs have litters of 3–4 hoglets (range 1–9) after a pregnancy of 34–37 days (Merck). Wild European hedgehogs have up to seven young, born between May and August (PTES).

When do baby hedgehogs open their eyes?

Hoglets are born blind. A pet hoglet's eyes open at 14–18 days (Merck). Wild European hoglets open their eyes and ears at about 2 weeks and can start to roll up at around the same age (Wildlife Online).

When do hoglets get quills?

Straight away. Wildlife Online describes about 100 soft white spines pushing through the skin within an hour of birth. A second set of darker spines starts to come through at 36–60 hours, and those baby spines are shed at about 6 weeks as the adult coat grows. Short fur appears by two to three weeks. These timings are published for European hoglets; pet hoglets follow a similar pattern, but vet sources don't give exact days.

When are hedgehogs weaned?

Pet hoglets start eating solid food at about 3 weeks and are weaned at 5–6 weeks; Merck advises separating them from their mother at about 8 weeks. Wild hoglets start on solids at 21–25 days and are weaned at about four weeks (PTES), fully by 6–8 weeks (Wildlife Online). Almost 20% of wild hoglets die before weaning (Morris 1977, via Wildlife Online), so a wild hoglet found alone needs a rescue's advice quickly.

Hoglet weight and growth chart (hedgehog age size chart)

This hoglet weight chart lists only the published figures we could verify. Where vet sources give no number, we say so rather than guess, so it's an honest hedgehog age size chart rather than a smooth curve.

For wild hoglets, three points are published: about 15 g at birth (8–25 g), roughly double that by one week, and about ten times birth weight by six weeks. The hoglet growth chart below draws those points as a line, with the published range shaded.

Pet hoglet weights are only published at birth (10–18 g, Merck) and in adulthood. One vet-reviewed pet site gives a monthly chart (about 1 oz at 1 month, 3.5 oz at 3 months and 9 oz at a year), but those figures sit far below Merck's adult weights of 300–600 g, so we don't use them. If you breed hedgehogs, weigh hoglets regularly on a gram scale and ask your exotic vet what gain to expect.

Juvenile hedgehogs

The juvenile stage runs from weaning to adulthood. For pets, that's about 6 weeks to 6 months; for wild hedgehogs, 6 weeks to their first birthday.

• Pets: African pygmy hedgehogs are sexually mature at just 2–3 months (Merck) — AnAge gives 84 days for females — and Merck advises separating hoglets from their mother at about 8 weeks and not breeding females before 6 months.
• Wild hedgehogs: independent youngsters spend their first summer and autumn feeding up. AnAge gives sexual maturity at about 253 days (8 months), which falls in mid-winter, so most breed for the first time the following spring.
• Autumn juveniles: wild hoglets from late litters may still be small in October and November. Current UK guidance is that healthy young hedgehogs over 450 g can survive hibernation, and those under 450 g from late October to February should be taken to a rescue (BHPS and partners, 2024) — our hibernation weight checker applies the guidance.

Adult hedgehogs and maturity

When do hedgehogs reach maturity? Sexually, very early: 2–3 months for pets (Merck) and about 8 months for wild European hedgehogs (AnAge). Physically, later: a vet-reviewed guide says pet hedgehogs keep growing until about 11 months.

So when is a hedgehog fully grown? At about 11 months for a pet. Adult pet females usually weigh 300–400 g and males 400–600 g (Merck). Wild European adults weigh 450–1,500 g and are 22–28 cm long (PTES), and their weight swings with the seasons — heaviest before hibernation, lightest in spring.

Adulthood is the longest stage. For pets it runs from about 6 months to 3 years; for wild hedgehogs from 1 to 5 years, though most wild hedgehogs die before they get far into it (average lifespan about 2 years, PTES). How long each kind usually lives is covered on our pet hedgehog lifespan calculator and wild hedgehog survival explorer.

Senior hedgehogs: signs of an old hedgehog

What is a senior hedgehog age? For pets, we use 3 years, because that's when Merck says tumours and heart disease become most common. For wild hedgehogs, we use 5 years, since only a small percentage live that long (PTES).

Signs of an old hedgehog overlap with signs of illness, so none of them proves age. Things owners and vets look out for in older pets include:

• Lumps, swellings or bleeding: tumours are very common, most often after age 3, and more than 80% are malignant (Merck).
• Weight loss or eating less: can follow dental disease, which is common in hedgehogs (Merck, RVC), or other illness.
• Tiring quickly or breathing changes: heart disease is typically seen from about age 3 (Merck).
• Less use of the wheel and more sleep. Normal slowing down, or a sign of pain — let your vet decide.
• Wobbling: not a normal sign of ageing. Wobbly Hedgehog Syndrome can start at any age (Merck), so see a vet.

Older pets benefit from more frequent weighing, softer food if chewing gets hard (ask your vet first) and a warm, easy-to-move-around enclosure.

Hedgehog age chart (hedgehog years to human years)

This hedgehog age chart converts hedgehog years to human years for pet and wild hedgehogs, using the same numbers as the calculator. A 1-year-old pet hedgehog is about 24.1 in human years, a 3-year-old about 48.6 and a 5-year-old about 73.1. For a wild hedgehog, the hedgehog age in human years rises more slowly: about 18 at 1, 36.4 at 3 and 54.7 at 5.

Ages past about 8 for pets and 10 for wild hedgehogs are very rare, so the high numbers there are only a playful comparison. The pet record is 11.4 years in captivity (AnAge); the wild record is 16 years (Rasmussen et al. 2023).

How old is my hedgehog? Telling age by weight and signs

If you've found a hoglet or adopted a hedgehog with no records, you're probably asking "how old is my hedgehog?". The second mode of the calculator combines the clues below into an age range. Here's how to tell a hedgehog's age, and the limits of each clue:

• Eyes: closed means under about 2 weeks (wild) or 14–18 days (pet, Merck). This is the clearest clue in the first weeks.
• Eating solids: hoglets start at about 3 weeks (Merck; 21–25 days for wild hoglets, Wildlife Online). One that's only suckling is younger than that.
• Quills: soft white spines only means a day or two old; a mix of white and darker spines means under about 6 weeks; a full adult coat means about 6 weeks or more (Wildlife Online).
• Weight: useful for wild hoglets up to about 6 weeks. On the calculator, a 30 g wild hoglet with open eyes comes out at 14–15 days, and a 200 g wild hedgehog at 5 weeks+. For pets, vet sources publish only birth and adult weights, so weight alone can tell a hoglet from an adult but not much more. A pet with open eyes that isn't yet eating solids comes out at 14 days – 3 weeks.

So, how old is a baby hedgehog? The clues can usually pin a hoglet down to within a week or two. But once a hedgehog is adult-sized — about 300 g for a pet, or 450 g for a wild hedgehog — its exact age can't be estimated from weight or looks. A breeder's or rescue's records are the only reliable guide. Scientists age dead wild hedgehogs by counting growth lines in thin slices of the jawbone, one line per winter (Rasmussen et al. 2023), but that isn't possible in a living animal.

If the hoglet is wild and alone, don't try to raise it: call a hedgehog rescue (BHPS: 01584 890 801 in the UK). Very young hoglets can't even go to the toilet without their mother's help until about 3–4 weeks old (Wildlife Online), so they need specialist care.

Hedgehog life cycle for kids (quick summary)

Here is the hedgehog life cycle for kids in four simple steps. It's short enough for a school project, and the box prints neatly on its own.

How this hedgehog age calculator works

No veterinary body publishes a way to convert hedgehog years to human years, and the charts online disagree: for a 3-year-old hedgehog we found 40 (a breeder's chart, Critter Connection) and about 60 (another online chart). We use a method that ties the numbers to biology, as on our other exotic-pet pages:

• Sexual maturity ≈ 12 human years (puberty). Pets mature at 2–3 months (Merck), so we use 2.5 months. Wild hedgehogs mature at about 253 days (AnAge).
• Young adult ≈ 18. Pets at 6 months, when Merck says females can first be bred; wild hedgehogs at 1 year, their first breeding season.
• End of a typical life ≈ 73.1, the WHO global human life expectancy. For pets that's 5 years, the middle of the Merck and VCA 4–6 year range. For wild hedgehogs we use 7 years, the start of AnAge's "up to 7–8 years" in the wild. The wild average of about 2 years reflects accidents, not ageing, so it would make wild hedgehogs "age" far too fast.

Between those points we draw straight lines, and after them we keep the same rate. That puts a 1-year-old pet at about 24.1 and a 3-year-old at about 48.6, in the middle of the published charts. The alternative — simply scaling by lifespan (73.1 ÷ 5 ≈ 14.6 human years per pet hedgehog year) — would make a sexually mature 3-month-old hedgehog only about 4 in human years, which doesn't fit.

The life stages come from the sources on this page: hoglet to 6 weeks (weaning), juvenile to 6 months (pets) or 1 year (wild), adult to 3 years (pets, when tumours and heart disease become common) or 5 years (wild), then senior. The "How old is my hedgehog?" mode turns each clue into an age window — eyes, solid food, quills and weight — and keeps the range they agree on, dropping the least reliable clue if two conflict. Its limits: human years compare life stages and aren't a biological measurement, and no clue can age an adult hedgehog.

Frequently asked questions

This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.