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Puppy Predictor

Bullmastiff Size Calculator

How big will my Bullmastiff get? Predict adult weight and track your puppy's development.

Breed Overview

About the Bullmastiff

Affectionate, loyal, and brave

Group

Working

Size Category

Giant

Lifespan

7-9 years

Full Maturity

24 months

Temperament Traits

DocileReliableDevotedLoyalReservedAlert

Growth & Height Benchmarks

Expected Adult Weight

100-130lbs

Typical Male

100-130 lbs

25-27" tall

Typical Female

100-130 lbs

24-26" tall

How the Bullmastiff Calculator Works

1

High-Sensitivity Dynamic Modeling

We use a proprietary High-Sensitivity Dynamic Model calibrated specifically for Bullmastiff development. This accounts for the biological reality that growth velocity decelerates sharply as a puppy matures, ensuring pinpoint accuracy for both 8-week-old puppies and older teenagers.

2

Maturity Window Calibration

A Bullmastiff typically reaches its full skeletal structure around 24 months. Our algorithm applies a specific maturity multiplier that adjusts the projection as your puppy approaches this target window.

3

Standard Deviation Check

Every projection is cross-referenced against the Bullmastiff breed standard (100–130 lbs). While estimates can begin at 6 weeks, data collected after the 12-week mark provides the highest statistical confidence.

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