Weighing a very small puppy
With a Chihuahua every ounce counts, so use a kitchen or baby scale rather than a bathroom scale, and type the weight with decimals: 1 lb 11 oz is 1.7 lb. In metric, switch to kg and use decimals of a kilogram (0.77 kg is 770 g).
The toy curve comes from breeds whose adults typically weigh under 12 lb. Toy pups start closer to their adult size than big ones: at 8 weeks about a quarter and at 16 weeks about half, where a large-breed pup has 15% and 40%.
Reading it against the standard
The AKC sets only a ceiling, 6 pounds, so the chart below follows a pup heading for 4.5 lb, three quarters of it. The example weigh-in, 1.7 lb at 12 weeks, lands on about 4.5 lb, with 3.3 to 6.6 lb as the likely spread.
In this data, toy dogs kept gaining after their first birthday more than bigger dogs did: a one-year-old toy dog was typically at 88% of what it went on to weigh at two to three years old. A Chihuahua that looks finished at ten months may still put on a few ounces, whether by growing or by filling out. If your puppy is very small, gains slowly or seems weak, ask your vet promptly.
Chihuahua puppy weight chart
| Age | Chihuahuaadult ≈ 4.5 lb | Share of adult weight |
|---|---|---|
| 8 weeks | 1.2 lb · 0.5 kg | 26% |
| 10 weeks | 1.4 lb · 0.6 kg | 31% |
| 12 weeks | 1.7 lb · 0.8 kg | 38% |
| 16 weeks | 2.2 lb · 1 kg | 50% |
| 5 months | 2.9 lb · 1.3 kg | 64% |
| 6 months | 3.2 lb · 1.4 kg | 71% |
| 7 months | 3.4 lb · 1.6 kg | 76% |
| 8 months | 3.6 lb · 1.6 kg | 80% |
| 9 months | 3.7 lb · 1.7 kg | 83% |
| 10 months | 3.8 lb · 1.7 kg | 85% |
| 1 year | 4 lb · 1.8 kg | 88% |
| 15 months | 4.1 lb · 1.9 kg | 91% |
| 18 months | 4.2 lb · 1.9 kg | 93% |
| 2 years | 4.4 lb · 2 kg | 97% |
| Adult (2–3 years) | 4.5 lb · 2 kg | 100% |