Why isn't my crested gecko growing or how big do they get?

Adult size and growth timeline

Crested geckos (Correlophus ciliatus) are mid-sized geckos. Per the PetMD crested gecko care sheet and the Pangea growth reference:

Females average slightly larger than males. Most weight gain happens in the first 18 months on a steady CGD diet. Growth past year 2 is minimal — well-fed adults gain very little additional weight.

Why juveniles stall

Slow or stalled growth in juveniles usually traces to husbandry:

• Inadequate CGD intake. Wrong consistency (too thick, too thin), refused brand/flavour, mix too old (discard after 24 hours), insufficient frequency (juveniles need daily access).
• Low temperatures. Below 70 °F / 21 °C ambient slows metabolism and feeding response. Target 72–78 °F.
• Recent rehoming stress. 1–4 weeks of slowed feeding is common after arrival; growth catches up.
• Refusal to feed reliably. Some hatchlings take 1–2 weeks to accept CGD; persistent refusal needs investigation.
• Stress from environment. Too small enclosure, no hides, visible neighbouring pets, high traffic location.
• Less often: parasites or underlying illness.

Verify husbandry first. Most stalled-growth cases resolve within 2–4 weeks of corrected setup.

Tracking weight

Weekly weighing through year one catches growth issues early:

• Use a 0.1 g precision scale (jewellery scale) — kitchen scales rounding to 1 g miss meaningful changes in geckos under 30 g.
• Place gecko in small lidded container — tare with container empty.
• Same day of week for consistency.
• Same conditions — pre-feeding or post-feeding, your choice but consistent.
• Log every reading. The chart is more useful than any single weight.

A steady upward trend through year one is the signal of healthy growth. Stagnant weight or weight loss is the signal to investigate.

Sexing crested geckos

Visible hemipenal bulge at the base of the tail in males appears at 6–12 months. Females have no bulge. Sexing is reliable from 4–6 months; harder in younger juveniles.

Some breeders sex earlier (3–4 months) by close examination, but 4–6 months is the standard reliable age. Most pet shops sex geckos at this age or older.

Pre-bulge sex prediction by egg incubation temperature is unreliable in crested geckos (unlike some lizard species where temperature-dependent sex determination is reliable).

Tail loss doesn't affect growth

Crested geckos can drop their tails as a defensive response (caudal autotomy) but — unlike many gecko species — do NOT regrow them. A tailless "frog-butt" gecko:

• Is otherwise healthy.
• Lives a full lifespan (15–20+ years).
• Has no quality of life impact from the missing tail.
• Reaches normal adult weight and length (snout-to-vent excludes tail).

Common causes of tail drop:

• Grabbing the tail during handling (most common).
• Sudden startle.
• Pursuit by a perceived predator.
• Rough handling during stress events.

Avoid by handling crested geckos gently from the body, never grasping the tail, and minimising handling during shed or other stressful periods. See crested gecko dropped tail for the full discussion.

Morph and size

Modest morph variation:

• Standard wild-type morphs reach typical 35–60 g range.
• Some designer morphs (Lillywhite, certain extreme line breeding) may average slightly smaller.
• Genetics from large parental lines produces larger offspring.

The variation is small (5–10 g typical range) and doesn't affect care requirements. All morphs eat the same CGD, live in the same enclosures, and grow on similar timelines.

When growth is too fast

Crested geckos over 70 g in good muscular condition are at the upper edge of normal. Approaching 80–100 g indicates obesity from over-feeding:

• Excessive insect feedings alongside CGD.
• Fatty insect feeders (waxworms, superworms) as more than occasional treats.
• CGD with daily insect supplements instead of 1–2×/week.

The fix:

• Reduce insect cadence to 1×/week maximum.
• Eliminate fatty treats.
• Continue CGD at standard 3×/week schedule.
• Monitor weight monthly; expect slow weight reduction over months if obesity has been chronic.

Obese crested geckos develop fatty liver disease and shortened lifespans. Catch the trend early on the weight chart.

When growth is too slow

Concerning signs in a juvenile:

• Weight under 25 g at 12 months suggests inadequate growth.
• Visible spine, thin tail base, prominent hip bones.
• Sagging belly (dehydration or malnutrition).
• Head looking large relative to body (chronic stunting).
• Lethargy beyond normal day-rest pattern.
• Reduced shed frequency (shed cycle linked to growth).

Vet consultation is warranted if any combination of these appears. A reptile-experienced vet can assess body condition, check for parasites, and rule out underlying illness.

Geriatric size

Older crested geckos (10+ years) typically maintain weight or lose slightly:

• Adult weight (35–60 g) is usually maintained.
• Slight loss in late life is normal.
• Significant loss with other warning signs is concerning.

Monitor monthly in geriatric geckos. Older geckos may benefit from slightly thinner CGD (easier to eat), more frequent weighing, and reduced handling.

Lifespan context

A growth chart for a 15–20+ year-lived species shows that growth is a year-one-and-two phenomenon; the remaining 13–18+ years are stable adulthood. The husbandry that supports good growth in year one (CGD, temperatures, humidity, low stress) is the same husbandry that supports a long stable adulthood.

For broader care and lifespan, see crested gecko care guide. For diet, see crested gecko diet. For refusal to feed, see crested gecko not eating.

The summary framing

Crested geckos grow from 2–3 g hatchlings to 35–60 g adults over 18–24 months, then maintain weight for the remaining 13–18+ years of their lifespan. Growth issues in juveniles usually trace to husbandry — wrong CGD, low temperatures, stress — and resolve when fixed. Track weight weekly through year one.