Pitbull Puppy Weight Chart — APBT, AmStaff & Pit Mix Growth

Expected weight for American Pit Bull Terrier, AmStaff, and Pit mix puppies from 8 weeks to adult. Adults: males 35–65 lb (APBT) or 55–70 lb (AmStaff); females 30–55 lb. Medium-breed growth curve — full size by 12–18 months.

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Age (months)

Current weight (lb, optional)

Expected at month 6

32-44 lb (avg 38)

American Pit Bull Terrier growth chart

Month	Expected (lb)
0	1.5
1	5
2	10
3	17
4	24
5	32
6	38
7	43
8	47
9	50
10	52
11	53
12	54

How to use the Pitbull puppy weight chart

Weigh weekly through 6 months — Growth trend matters more than single measurement.
Pick breed type — APBT (smaller), AmStaff (larger), Staffy (smallest), or Pit mix.
Compare to breed percentile — Wide normal range — mid-percentile is the target.
Switch to adult food at 12–14 months — Pitbulls finish growing earlier than larger breeds.

Pitbull growth curve by month (APBT reference)

Age	Male (lb)	Female (lb)
8 weeks	10–12	9–11
12 weeks	18–22	16–20
4 months	26–32	23–28
6 months	32–42	28–38
9 months	40–52	35–46
12 months	45–58	38–50
18 months	48–62	40–52
Adult (24+ mo)	35–65	30–55

For AmStaff-type Pitbulls, add approximately 15 % to these values; for Staffordshire Bull Terriers, subtract approximately 25 %.

Why Pitbull sizes vary so widely

“Pitbull” is not a single recognized breed but a loose colloquial grouping of related bully-type breeds and mixes. The four most commonly called “Pitbulls”:

American Pit Bull Terrier (APBT): UKC-registered; adults 35–65 lb males, 30–50 lb females. Originally bred for farm work and pit fighting; now pet companions + sport dogs.
American Staffordshire Terrier (AmStaff): AKC-registered; adults 55–70 lb males, 40–55 lb females. Stockier and heavier than APBT.
Staffordshire Bull Terrier (Staffy): English breed, AKC recognized; adults 24–38 lb. Smallest and most compact.
American Bully: XL, Standard, Classic, Pocket, Extreme variants — 30–120+ lb depending on type. Recently recognized by UKC (2013).
Shelter “Pit mix”: Often a mix of these breeds with Boxers, Mastiffs, or other bully types. Size unpredictable.

Without breed registration documentation, predicting adult size from an 8-week-old puppy is unreliable. The general rule: adult weight is approximately 4–5× the 8-week weight, but the wide genetic variance means this can be off by 10–15 lb either way.

Frequently Asked Questions

How much should a Pitbull puppy weigh at each age?

Male Pitbull puppy weights: 8 weeks 10–12 lb; 12 weeks 18–22 lb; 16 weeks 26–32 lb; 6 months 32–42 lb; 9 months 40–55 lb; 12 months 45–58 lb. Female Pits track 10–15 % lighter. Adults: males 35–65 lb, females 30–55 lb. Pitbulls have wide variance because “Pitbull” is not a single breed but covers APBT, AmStaff, Staffy, and mixes.

When do Pitbulls stop growing?

Pitbulls reach about 90 % of adult weight by 12 months and finish filling out by 18 months. Muscle mass continues developing through age 3 — a 2-year-old Pit that looks “lanky” will often fill out noticeably over the next year. Skeletal growth plates typically close by 12–15 months. Switch to adult food at 12–14 months.

What's the difference between APBT, AmStaff, and Staffy size?

American Pit Bull Terrier (UKC-registered): adults 35–65 lb males, 30–50 lb females. American Staffordshire Terrier (AKC): adults 55–70 lb males, 40–55 lb females (AmStaffs are heavier). Staffordshire Bull Terrier (English breed): smaller at 24–38 lb. “Pit mix” or “shelter Pitbull” is often AmStaff-leaning and falls in the 45–70 lb range. Use the calculator with the specific breed registered for most accurate projection.

My Pitbull puppy is smaller than the chart — is that a problem?

Usually not, unless significantly below the 10th percentile for several weekly measurements. Pitbulls vary widely because the breed encompasses several size types. Rescue or backyard-bred Pits have especially unpredictable adult sizes. Monitor growth trend over 4+ weeks — a puppy steadily gaining at its own percentile curve is fine even if below average. Concerning: weight loss, flat-lining growth curve, lethargy, or any change in appetite.

How much should I feed a Pitbull puppy?

Standard all-life-stages or puppy formula (large-breed puppy formula not strictly needed — Pits are medium, not large-breed). Feed 3–4 meals/day through 6 months, then 2–3 meals. Approximate calorie needs: 3 months 750–1,000 kcal/day; 6 months 1,000–1,500 kcal; 9 months 1,100–1,600 kcal; 12 months transition to adult. Target mid-percentile growth for the breed.

When should I spay/neuter a Pitbull?

Current AAHA guidance for medium-breed dogs (under 45 lb adult): neuter at 6 months; spay females before first heat cycle. Larger AmStaff-type (45+ lb adults): wait until 12–18 months to allow growth-plate closure, which reduces orthopedic disease risk per recent research. Always discuss with your vet — behavioral factors (intact-male aggression, unwanted breeding) may tip the balance toward earlier altering.

Sources & References

[1]
UKC American Pit Bull Terrier Standard — United Kennel Club
[2]
AKC American Staffordshire Terrier — American Kennel Club
[3]
ASPCA Position on Pit Bulls — ASPCA
[4]
Spay/Neuter Timing in Medium-Breed Dogs — American Animal Hospital Association