Last updated: July 19, 2026
This calculator checks your bearded dragon's weight against age-appropriate ranges. Enter their current weight in grams and select their age to see whether they're on track. Healthy bearded dragons typically reach 350–550 grams as adults (18+ months).
Bearded dragons grow quickly in their first year, then slow down as they approach adult size. This chart shows typical weight ranges at each growth stage. Individual dragons vary — genetics, diet, and husbandry all affect growth rate.
| Age | Weight (grams) | Weight (oz) | Length (inches) |
|---|---|---|---|
| 0–1 month (hatchling) | 4–6g | 0.1–0.2 oz | 3–4" |
| 1–2 months | 6–40g | 0.2–1.4 oz | 5–9" |
| 2–3 months | 20–100g | 0.7–3.5 oz | 8–11" |
| 3–4 months | 50–115g | 1.8–4.1 oz | 9–12" |
| 4–5 months | 60–150g | 2.1–5.3 oz | 11–16" |
| 5–6 months | 100–200g | 3.5–7.1 oz | 13–18" |
| 6–8 months | 150–280g | 5.3–9.9 oz | 16–20" |
| 8–12 months (juvenile) | 200–360g | 7.1–12.7 oz | 18–22" |
| 12–18 months (sub-adult) | 300–450g | 10.6–15.9 oz | 20–24" |
| 18+ months (adult) | 350–550g | 12.3–19.4 oz | 20–24" |
Proper husbandry is the foundation of healthy growth. Temperature, UVB lighting, and diet all directly affect your bearded dragon's weight and development.
For overall reptile health, check our Reptile Weight Calculator for other species, or use the Reptile Nutrition Calculator for feeding guidelines.
Bearded dragons pass through four broad life stages, and each one has a different weight profile and different care priorities. Knowing which stage your dragon is in helps you judge whether their weight is on track or a sign that something needs adjusting.
Starting around 4–6 grams, hatchlings are fragile and eat almost constantly. They need small, appropriately sized insects several times a day and daily calcium dusting. Slow weight gain at this stage often points to temperature or feeding problems.
This is the fastest growth window. A healthy juvenile can gain 50–100 grams per month between 3 and 8 months, driven by an insect-heavy diet. Weekly weigh-ins are most useful here for catching plateaus early.
Growth slows noticeably as your dragon approaches full length. The diet should be shifting toward more greens and fewer insects to prevent excess fat gain while the frame finishes filling out.
Weight stabilizes in the 350–550 gram range. The goal is maintenance: steady weight, a plant-forward diet, and monitoring for slow creep upward (obesity) or unexpected drops (illness).
The number on the scale is only part of the picture. Body condition — how your dragon looks and feels — tells you whether that weight is muscle and healthy fat or a warning sign. Check these visual cues alongside the calculator result.
Here are three common scenarios that show how to interpret the calculator against the age chart above. Use them as a guide for what action, if any, your own reading calls for.
Example 1: 5-month-old at 90g
The 4–5 month range is 60–150g, so 90g is comfortably in range. This dragon is growing normally. Keep the insect-heavy juvenile diet and weigh weekly to confirm continued gains.
Example 2: 8-month-old at 140g
The 6–8 month range is 150–280g, so 140g is slightly under. This is worth investigating: check basking temperature (100–110°F), UVB age, and whether the dragon is eating enough insects. A vet visit rules out parasites if it fails to catch up.
Example 3: Adult male at 600g
Adult range tops out around 550g, so 600g suggests overweight, especially if paired with fat pads and a bulging belly. Cut fatty feeders like waxworms, raise the greens ratio to 70–80%, and add out-of-enclosure exercise.
Sex has a measurable effect on adult size. Males are generally heavier and longer, so a female sitting at the lower end of the adult range is not necessarily underweight. Use these averages to set realistic expectations for your dragon.
| Trait | Male | Female |
|---|---|---|
| Adult weight | 400–550g | 350–500g |
| Adult length | 20–24" | 18–22" |
| Head shape | Wider, more triangular | Narrower |
| Femoral pores | Larger, more prominent | Smaller |
| Gravid weight swing | None | Can gain 30–70g when carrying eggs |
A note on egg-laying: females can put on significant weight when gravid (carrying eggs), even without mating, then drop it after laying. A sudden gain in a mature female followed by digging behavior is usually eggs, not obesity.
When a weigh-in falls outside the expected range, the cause usually traces back to husbandry, diet, or health. Work through these common factors before assuming genetics.
If husbandry and diet look correct and weight still trends the wrong way over two or three weigh-ins, book a reptile veterinarian. Rapid or unexplained weight loss in particular should never be ignored.
Consistency matters more than any single reading. Small day-to-day swings from food, water, or a recent bowel movement are normal, so the trend across weeks is what you track. These habits keep your numbers reliable.
FAQs
Adult bearded dragons (18+ months) typically weigh 350–550 grams (12–19 oz). Males are usually larger at 400–550g while females average 350–500g. Weight varies by genetics, diet, and overall health. Use our calculator to check against age-specific ranges.
Bearded dragons grow rapidly in their first 12 months, gaining 50–100 grams per month during peak growth (3–8 months). Growth slows after 12 months and most reach adult size by 18–24 months.
Use a digital kitchen scale set to grams. Place a small container on the scale, tare (zero) it, then gently place your bearded dragon inside. Weigh at the same time each day for consistency — before feeding is ideal.
Underweight bearded dragons may have parasites, improper husbandry (wrong temperatures or UVB), or inadequate diet. Ensure basking temps are 100–110°F, offer appropriately sized insects dusted with calcium, and consult a reptile veterinarian.
Overweight bearded dragons are common when fed too many fatty insects (waxworms, butterworms) or too little exercise. Reduce fatty treats, increase greens to 70–80% of adult diet, and encourage activity outside the enclosure.
Weigh juveniles (under 12 months) weekly to track growth. Adults can be weighed bi-weekly or monthly. Record weights to spot trends — sudden weight loss or failure to gain during growth phases warrants a vet visit.
Healthy hatchlings grow from about 4g at birth to 200–360g by 12 months. The fastest growth happens between 3–8 months. If your bearded dragon plateaus during this period, check temperatures, UVB output, and diet quality.
Yes. Adult males typically weigh 400–550g and measure 20–24 inches, while females average 350–500g and 18–22 inches. Males also have wider, more triangular heads and larger femoral pores.
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