Leopard geckos hatch at about 3–4 in and 2–5 g and reach full size at about 18 months. Adult males are usually 8–10 in and 60–90 g, and females 7–8 in and 45–70 g. For example, a 6-month-old is usually 5.3–6.3 in (13–16 cm) and 20–30 g, and a 1-year-old male 7–9 in (18–23 cm) and 50–75 g.
Estimates only. Every leopard gecko grows at its own pace, depending on food, temperature, sex and genetics. See a reptile vet if your gecko is losing weight, has a thinning tail or looks unwell.
How big do leopard geckos get?
Leopard geckos are small, sturdy lizards. A healthy adult is usually 7–10 inches (18–25 cm) long from nose to tail tip, and weighs about 45–90 grams. Arbor View Animal Hospital's vet guide gives 7–10 inches, with females typically smaller than males. ReptiFiles gives the same 7–10 in (17–25 cm). LafeberVet's veterinary sheet says mature males weigh 60–90 g, while females may be as light as 45 g. That's the short answer to "leopard gecko, how big do they get?": about the length of a new pencil.
Other sources frame adult leopard gecko size a little differently. VCA Animal Hospitals gives a wider 5–10 in (12–25 cm), and LafeberVet a narrower 6.5–8 in (16.5–20 cm). The Animal Diversity Web says adults reach about 220 mm (8 in) and occasionally 10 in, "although this is rare". Selectively bred giant morphs are the exception, and we cover them below.
Leopard gecko full grown size at a glance
- Hatchling: 3–4 in (8–10 cm) and 2–5 g (0.1–0.2 oz).
- Adult male: 8–10 in (20–25 cm), 60–90 g (2.1–3.2 oz).
- Adult female: 7–8 in (18–20 cm), 45–70 g (1.6–2.5 oz).
- Full size reached: at about 18 months; PetMD says growth stops at around 1.5 years.
- Giant / super giant: roughly 9–12.5 in, with super giant males over 110 g (Tremper's giant FAQ).
Total length includes the tail, and a leopard gecko's tail is a big part of it. Arbor View describes the tail as the gecko's energy reserve. A gecko that has dropped its tail will measure shorter, and the regrown tail is usually stubbier, so leopard gecko length alone can mislead.
Leopard gecko growth chart (size by age)
This leopard gecko growth chart shows typical total length and weight for males and females from hatching to adulthood. Use it as a leopard gecko size chart to check whether a young gecko is on track and to compare with the calculator's result for any age in between.
| Age | Male length | Male weight | Female length | Female weight | Life stage |
|---|---|---|---|---|---|
| Hatchling | 3–4 in (8–10 cm) | 2–5 g | 3–4 in (8–10 cm) | 2–5 g | Hatchling |
| 1 month | 3.4–4.4 in (9–11 cm) | 5–9 g | 3.4–4.4 in (9–11 cm) | 5–9 g | Hatchling |
| 2 months | 3.9–4.9 in (10–12 cm) | 8–14 g | 3.9–4.9 in (10–12 cm) | 8–14 g | Juvenile |
| 3 months | 4.3–5.3 in (11–14 cm) | 11–18 g | 4.3–5.3 in (11–14 cm) | 11–18 g | Juvenile |
| 6 months | 5.3–6.3 in (13–16 cm) | 20–30 g | 5.3–6.3 in (13–16 cm) | 20–30 g | Juvenile |
| 9 months | 5.9–6.9 in (15–18 cm) | 29–39 g | 5.9–6.9 in (15–18 cm) | 29–39 g | Sub-adult |
| 12 months (1 year) | 7–9 in (18–23 cm) | 50–75 g | 7–8 in (18–20 cm) | 45–60 g | Adult |
| 18 months (1.5 years) | 8–10 in (20–25 cm) | 60–90 g | 7–8 in (18–20 cm) | 45–70 g | Adult |
| 2 years and older | 8–10 in (20–25 cm) | 60–90 g | 7–8 in (18–20 cm) | 45–70 g | Adult (fully grown) |
No vet school publishes a month-by-month leopard gecko chart, so this one is built from life-stage sizes and says where each number comes from. Hatchling sizes come from the Animal Diversity Web and Wikipedia (3–4 in total length; PetMD's 1.5–2 in looks like body length without the tail) and PetMD (2–5 g). Juvenile and sub-adult sizes are PetMD's, placed in the middle of each stage (4.5 and 9.5 months). The 12-month row uses PetMD's adult threshold (7+ in, 50+ g) with keeper-chart lengths. The adult row (18 months, flat after) uses LafeberVet's weights and The Vet Desk's "males 8 to 10, females 7 to 8 inches". Months in between are straight lines between those points.
The leopard gecko growth chart below plots the weight columns. The solid green line is the typical male weight and the dashed purple line the typical female weight, with each sex's normal range shaded.
Two things stand out. The lines rise steeply for the first year, from about 2–5 g at hatching to about 60 g at 12 months. Then the sexes separate: by 18 months a typical male is about 75 g and a typical female about 58 g, and both lines go flat.
Leopard gecko weight chart: how much should a leopard gecko weigh?
Weight is the most useful number to track at home, because it changes faster than length and a kitchen scale reads it in seconds. This leopard gecko weight chart lists the anchor weights behind the growth chart (both sexes combined), with ounces and the source for each.
| Age | Typical weight | Ounces | Source |
|---|---|---|---|
| Hatchling | 2–5 g | 0.1–0.2 oz | PetMD and Wikipedia: 2–5 g at hatching |
| 2 months | 8–14 g | 0.3–0.5 oz | End of PetMD's hatchling stage |
| 4.5 months | 15–25 g | 0.5–0.9 oz | PetMD juvenile (2–7 months): 15–25 g |
| 9.5 months | 30–40 g | 1.1–1.4 oz | PetMD sub-adult (7–12 months): 30–40 g |
| 12 months (1 year) | 45–75 g | 1.6–2.6 oz | PetMD: adult from 12 months, 50+ g |
| 18 months (1.5 years) | 45–90 g | 1.6–3.2 oz | LafeberVet: males 60–90 g, females from about 45 g |
So how much should a leopard gecko weigh? An adult usually weighs 45–90 g (1.6–3.2 oz): males about 60–90 g and females about 45–70 g. PetMD uses 50 g or more as its adult benchmark. For leopard gecko weight by age before adulthood, a 6-month-old is usually 20–30 g and a 9-month-old 29–39 g.
A single weigh-in matters less than the trend. Weigh your gecko once a month at about the same time, before a meal, and note it down. A young gecko should keep gaining. An adult should hold roughly steady, and steady loss at any age is a reason to see a vet.
Male vs female leopard gecko size
Males are bigger. Arbor View notes that females are typically smaller than males. LafeberVet's adult weights show the gap: mature males weigh 60–90 g, while females may be as light as 45 g. Wikipedia, summarizing published measurements, gives adult females 18–20 cm (7.1–7.9 in) and 50–70 g, and males 20–28 cm (7.9–11 in) and 60–80 g.
The sexes look the same while young. On our chart they share one curve until about 9 months and separate as they mature, which PetMD and Arbor View put at 9–18 months. At 12 months a typical male is 7–9 in (18–23 cm) and 50–75 g; a typical female 7–8 in (18–20 cm) and 45–60 g. By then a male has reached about 89% of adult length and a female about 100%.
Not sure of the sex? Arbor View notes that males have more prominent femoral pores and a hemipenal bulge, which become visible as the gecko matures. Choose "Not sure" in the calculator and it uses the full range for both sexes.
Giant and super giant leopard geckos
"Giant" in leopard geckos is a specific bred trait, not just a big individual. It traces back to breeder Ron Tremper's line, and his Giant Leopard Gecko FAQ classifies geckos by weight at one year:
- Giant: males 80–110 g and females 60–90 g by one year of age, with adult males expected at about 90–110 g.
- Super giant: males over 110 g and females over 90 g by one year. The original super giant, a male called Moose, reached 156 g and about 11⅛ in.
Breeder and keeper pages describe giant leopard gecko size as roughly 9–11 inches, and a super giant leopard gecko as up to about 12.5 inches. Those length figures come from breeders rather than vets, so treat them as approximate.
| Morph | Weight at 12 months | Adult male length | Adult weight |
|---|---|---|---|
| Normal | 50–75 g / 45–60 g | 8–10 in | 60–90 g / 45–70 g |
| Giant | 80–110 g / 60–90 g | 9–11 in | 90–110 g / 60–90 g |
| Super giant | 110–125 g / 90–110 g | 10–12.5 in | 110–156 g / 90–125 g |
Weights from Tremper's giant FAQ (breeder site). Super giant upper limits (125 g at 12 months, 156 g for adult males, 125 g for adult females) and giant lengths at 12 months are our assumptions, capped by Moose's 156 g. Before about 9 months, the calculator uses the normal chart for every morph, because no source gives giant sizes for young geckos.
Baby, hatchling and juvenile leopard gecko size
Hatchling leopard gecko size is about 3–4 inches (7–10 cm). The Animal Diversity Web gives about 85 mm, and hatchlings weigh only 2–5 grams (PetMD; Wikipedia). PetMD's vet-reviewed article lists 1.5–2 inches for hatchlings. That figure most likely measures the body without the tail, so check how a size was measured before comparing.
Baby leopard gecko size in the first months changes faster in weight than in length. On our chart a 3-month-old is usually 4.3–5.3 in (11–14 cm) and 11–18 g, while a 6-month-old is 5.3–6.3 in (13–16 cm) and 20–30 g, about 68% of adult length.
Juvenile leopard gecko size, using PetMD's 2–7 month juvenile stage, is about 5 inches and 15–25 grams. Sub-adults (7–12 months) are about 6–7 inches and 30–40 grams. During these stages Arbor View recommends 2–3 food items daily for geckos under 6 months and no loose substrate. VCA advises feeding juveniles every 1–2 days.
How fast do leopard geckos grow and when do they stop growing?
How fast do leopard geckos grow? Fastest in the first year. On the chart, weight goes from about 2–5 g at hatching to 45–75 g at 12 months, a ten- to twentyfold gain, while length roughly doubles. Growth then slows sharply.
When do leopard geckos stop growing? PetMD says growth stops at around 1.5 years (18 months), and keeper charts agree that full length is reached by about 18 months. The Animal Diversity Web puts sexual maturity at about 18 months, or 16–24 months in captive-bred animals. After that, size is set, and a weight increase in an adult usually means fat rather than growth.
What affects leopard gecko growth?
- Warmth: Arbor View notes that leopard geckos need daytime basking temperatures for optimal growth, citing research that behavioural thermoregulation increases their growth rate. Arbor View suggests a basking spot of 95–100 °F.
- Food and supplements: live insects, gut-loaded and dusted with calcium (VCA, Arbor View). Too little calcium or vitamin D3 can cause metabolic bone disease, which stunts and deforms growing bones. Raising feeders for much smaller insect-eaters as well? See the flightless fruit fly culture planner.
- Sex and genetics: males grow bigger than females, and giant lines bigger than both (Tremper).
- Health: Arbor View notes that geckos with parasites are often thin. Regrowing a lost tail also costs energy, and Arbor View says it takes weeks.
- Feeding schedule: overfeeding speeds weight gain but not healthy growth. Arbor View lists obesity among the common problems in leopard geckos.
How old is my leopard gecko? Telling age by size
If your gecko came from a pet shop, a rescue or a previous owner without records, size is the best clue to its age while it is still growing. Switch the calculator to Size → age and enter its length, weight or both. The tool reads the growth chart backwards to give a leopard gecko age by size estimate. The best estimate is the age when a typical gecko reaches that size. The likely range runs from how early a fast grower and how late a slow grower would get there.
| Weight | Best estimate (sex unknown) | If male | If female |
|---|---|---|---|
| 3 g (0.1 oz) | about 0 weeks | under 2 weeks | under 2 weeks |
| 5 g (0.2 oz) | about 2 weeks | under 5 weeks | under 5 weeks |
| 10 g (0.4 oz) | about 8 weeks | 5 weeks – 3 months | 5 weeks – 3 months |
| 15 g (0.5 oz) | about 3 months | 2–5 months | 2–5 months |
| 20 g (0.7 oz) | about 5 months | 3–6 months | 3–6 months |
| 30 g (1.1 oz) | about 8 months | 6–10 months | 6–10 months |
| 40 g (1.4 oz) | about 10 months | 10–11 months | 10–11 months |
| 50 g (1.8 oz) | about 11 months | 10–12 months | 11 months or older |
| 60 g (2.1 oz) | Adult-sized | 11 months or older | Adult-sized: age can't be told |
| 75 g (2.6 oz) | Adult-sized | Adult-sized: age can't be told | Adult-sized: age can't be told |
| Length | Best estimate | Likely range |
|---|---|---|
| 3 in (8 cm) | about 0 weeks | under 0 weeks |
| 4 in (10 cm) | about 5 weeks | under 2 months |
| 5 in (13 cm) | about 3 months | 2–5 months |
| 6 in (15 cm) | about 7 months | 5–10 months |
| 7 in (18 cm) | about 10 months | 10 months or older |
| 8 in (20 cm) | Adult-sized | Adult-sized: age can't be told |
| 9 in (23 cm) | Adult-sized | Adult-sized: age can't be told |
For example, a 10 g gecko is most likely about 8 weeks old (5 weeks – 3 months), a 20 g gecko about 5 months, and a 30 g gecko about 8 months. A 50 g gecko reads differently by sex: as a female it is probably 11 months or older old, as a male probably 10–12 months old. Length gives a rougher answer, so a 5-inch gecko is probably 2–5 months old. If length and weight disagree, as with an 8-inch gecko that weighs only 20 g, the tool says so and widens the range (3 months or older). A long but light gecko may be underweight.
How to tell how old a leopard gecko is: the limits
- Adults can't be aged by size. Once a gecko reaches adult size at about 18 months, a 2-year-old and a 15-year-old can look the same. The calculator says so rather than guessing.
- Giants read older. Size → age mode uses the normal chart, so a giant or super giant will look older than it is.
- Tails change length. A regrown tail is usually shorter and fatter, so use weight when you can.
- Records beat estimates. Ask the breeder or shop for a hatch date. A reptile vet can give a professional opinion during a health check.
How big do geckos get? Pet gecko size comparison
How big do geckos get? Among the common pet species, most are 5–10 inches long. The tokay is the big exception among popular pets, and the leachie is the largest gecko of all. So how big can geckos get? ReptiFiles describes the leachie (Rhacodactylus leachianus leachianus) as the largest gecko in the world, at 14–17 inches (36–43 cm).
| Gecko | Adult length | Adult weight | Notes and sources |
|---|---|---|---|
| Leopard gecko | 7–10 in (18–25 cm) | 45–90 g | Ground-dwelling; Arbor View, ReptiFiles (length), LafeberVet (weight) |
| Crested gecko | 5–8 in (13–20 cm) | 35–45 g | Climbing; PetMD 5–8 in, ReptiFiles about 8 in and 35–45 g |
| African fat-tailed gecko | 7–10 in (18–25 cm) | — | Ground-dwelling; Tree of Life Exotics 7–9 in, ReptiFiles 8–10 in |
| Gargoyle gecko | 8–10 in (20–25 cm) | 45–65 g | Climbing; ReptiFiles |
| Tokay gecko | 8–16 in (20–41 cm) | — | Climbing; PetMD 8–16 in; Animal Diversity Web about 35 cm |
| Common house gecko | 3–6 in (8–15 cm) | — | Climbing; Animal Diversity Web 75–150 mm |
| Leachie (New Caledonian giant) gecko | 14–17 in (36–43 cm) | — | Largest gecko species, R. l. leachianus (ReptiFiles); the smaller R. l. henkeli is 9–12 in |
How big do crested geckos get?
Crested gecko size is a little smaller than a leopard gecko's in length. PetMD's care sheet gives 5–8 inches, and ReptiFiles says about 8 inches and 35–45 g. Crested geckos are climbers, though, so they need a tall enclosure (PetMD suggests at least 20 gallons) rather than a long, low one. So how big do crested geckos get? About the same as a small leopard gecko, but lighter.
What is the biggest pet gecko?
Of the commonly kept species, the biggest pet gecko by length is the tokay, at 8–16 inches (PetMD). The Animal Diversity Web calls it one of the largest living geckos, at around 35 cm. The leachie is bigger still, but it is a specialist's animal. Among ground-dwelling geckos, the leopard and African fat-tailed geckos are similar in size, and both sit near the middle of the range.
Leopard gecko tank size by age
Advice on leopard gecko tank size has changed a lot, which is why you will find answers from 10 to 120 gallons. Here is the current guidance and the older guidance side by side, organised as a leopard gecko enclosure size by age table:
| Stage | Gecko length | Current recommendation | Older guidance |
|---|---|---|---|
| Hatchling & juvenile (under 7 months) | 3–6 in | 36 × 18 × 18 in (91 × 46 × 46 cm), about 50 gallons — an adult-size setup with plenty of hides; no loose substrate | 10 gallons (VCA) |
| Sub-adult & adult (7 months +) | 6–10 in | 36 × 18 × 18 in (91 × 46 × 46 cm), about 50 gallons, at least 4.5 sq ft of floor (ReptiFiles); 30–40 gal, about 30 × 16 × 16 in (Arbor View) | 10 gallons, at least 6 in high (VCA); 10–20 gallons in many older guides (ReptiFiles) |
| Giant & super giant adults | 9–12.5 in | 36 × 24 × 18 in (91 × 61 × 46 cm) or 4 × 2 × 2 ft (ReptiFiles' 'better' and 'best' sizes) | — |
10 gallons or 36 × 18 × 18 in? Why the advice disagrees
Older guides set the bar by what a small gecko can survive in. VCA's care page says a single leopard gecko can be housed in a 10-gallon aquarium at least 6 inches high, and ReptiFiles notes that many care resources still say 10 or 20 gallons is enough. Newer, welfare-based guidance asks for far more. Arbor View Animal Hospital's 2021 vet guide sets 30–40 gallons (about 30 × 16 × 16 in) as the minimum, and ReptiFiles asks for at least 36 × 18 × 18 in with 4.5 square feet of floor. Both say a gecko is stressed by too much exposure, not by too much space, so a big enclosure needs plenty of hides and clutter.
Floor space matters more than height for this ground-dwelling species, and room for a proper warm-to-cool gradient matters most of all. A hatchling can live in the adult setup from the start if it has enough cover and no loose substrate. The calculator's enclosure suggestion follows this newer guidance and points giant morphs to ReptiFiles' larger "better" size.
Signs your leopard gecko is underweight or overweight
Charts tell you whether a gecko is the expected size for its age. Body condition tells you whether that size is healthy. This is general information, not a diagnosis:
- The tail is the gauge: Arbor View describes the tail as the gecko's energy reserve. A tail that keeps getting thinner means the gecko is using up its reserves.
- Underweight signs: weight loss, lethargy and a poor appetite are warning signs of illness (PetMD). Arbor View notes that geckos with parasites often look thin and may have diarrhea.
- Overweight signs: Arbor View lists obesity among leopard geckos' common problems. An adult whose weight keeps climbing after 18 months is gaining fat, not growing. Check feeding frequency against VCA's guide of 2–3 meals a week for adults, and keep mealworms, waxworms and superworms as occasional extras (Arbor View).
- Weigh, don't guess: a monthly weight in grams makes slow changes visible long before you can see them.
See a reptile vet if your gecko keeps losing weight, refuses food with lethargy, has a shrinking tail, or is a female that looks swollen and stops eating (VCA warns that egg binding is an emergency). Arbor View recommends routine exams every 6–12 months.
How this leopard gecko size calculator works
Size → age: best estimate = age when a typical gecko reaches that size · range = ages when the fastest and slowest growers do
In Age → size mode the calculator converts weeks or years to months, then reads the length and weight range at that age from the growth chart above, drawing straight lines between chart points. "Not sure" uses the widest range across both sexes, and the morph setting switches to the giant or super giant adult sizes. "% of adult size" compares the typical length at that age with the middle of the adult range for that sex and morph (9 in for normal males, 7.5 in for females). The enclosure suggestion follows ReptiFiles' and Arbor View's minimums described above.
In Size → age mode it runs the normal chart in reverse. When the gecko is in the adult range and the best estimate is 12 months or more, it reports "adult-sized" and doesn't give an exact age. Because growth depends on food, warmth and genetics, treat every result as an estimate and a starting point for a conversation with your reptile vet. Want to know how your gecko's age compares in human years, or how long leopard geckos live? See the leopard gecko lifespan and age calculator. Keep other reptiles? Try the bearded dragon size by age chart or the ball python size calculator.
Frequently asked questions
How big do leopard geckos get?
Most adults are 7–10 in (18–25 cm) long (Arbor View, ReptiFiles) and weigh about 45–90 g (LafeberVet). On our chart adult males are 8–10 in (20–25 cm) and 60–90 g, and females 7–8 in (18–20 cm) and 45–70 g.
How big is a 6 month old leopard gecko?
Usually 5.3–6.3 in (13–16 cm) long and 20–30 g (0.7–1 oz). That's about 68% of adult length.
How big is a baby leopard gecko?
Hatchlings are about 3–4 in (7–10 cm) long and weigh 2–5 g (Animal Diversity Web, Wikipedia, PetMD). By 3 months a baby is usually 4.3–5.3 in (11–14 cm) and 11–18 g.
How big is a 1 year old leopard gecko?
A 1-year-old male is usually 7–9 in (18–23 cm) and 50–75 g; a female 7–8 in (18–20 cm) and 45–60 g. PetMD treats leopard geckos as adults from 12 months (7+ in, 50+ g).
When do leopard geckos stop growing?
At about 18 months. PetMD says growth stops at around 1.5 years, and keeper charts put full length at about 18 months. Weight gain in an adult after that is usually fat.
How fast do leopard geckos grow?
Fastest in the first year: weight rises from 2–5 g at hatching to about 45–75 g at 12 months on our chart, while length roughly doubles. Warmth, a varied calcium-dusted insect diet and good health all affect the speed.
How much should a leopard gecko weigh?
Adults usually weigh 45–90 g (1.6–3.2 oz): males about 60–90 g and females about 45–70 g (LafeberVet). A 6-month-old is usually 20–30 g.
Are male leopard geckos bigger than females?
Yes. Arbor View notes that females are typically smaller. LafeberVet gives mature males 60–90 g and females as light as 45 g, and Wikipedia gives males 20–28 cm and females 18–20 cm.
How big do giant leopard geckos get?
Tremper's giant FAQ classes giants as males 80–110 g and females 60–90 g by one year; super giants are over 110 g (males) and 90 g (females). Breeder pages put giants at about 9–11 in and super giants up to about 12.5 in. The original super giant, Moose, weighed 156 g.
How can I tell how old my leopard gecko is?
While it is growing, weight is the best clue: a 10 g gecko is probably 5 weeks – 3 months old and a 30 g gecko 6–10 months. Once a leopard gecko reaches adult size, at about 18 months, its exact age can't be estimated from size; breeder or seller records are the only reliable source.
How big do geckos get?
Most pet geckos are 5–10 in long: leopard geckos 7–10 in, crested geckos 5–8 in (PetMD), African fat-tailed geckos 7–10 in and gargoyle geckos 8–10 in. Tokays reach 8–16 in (PetMD), and small house geckos only 3–6 in (Animal Diversity Web).
How big can geckos get?
The largest gecko species, the leachie (New Caledonian giant gecko), reaches 14–17 in (36–43 cm) (ReptiFiles). Among popular pets, the tokay gecko is the biggest, at up to 16 in (PetMD).
What size tank does a leopard gecko need?
Current guidance is at least 36 × 18 × 18 in with 4.5 sq ft of floor (ReptiFiles), or 30–40 gallons, about 30 × 16 × 16 in (Arbor View Animal Hospital). Older guides, including VCA, say a 10-gallon tank for one gecko.
How big do crested geckos get?
About 5–8 in long (PetMD), or around 8 in and 35–45 g as adults (ReptiFiles), so a little lighter than a leopard gecko. They climb, so they need a tall enclosure.
This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.