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Puppy Predictor

Mastiff Size Calculator

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

Breed Overview

About the Mastiff

Courageous, dignified, and good-natured

Group

Working

Size Category

Giant

Lifespan

6-10 years

Full Maturity

24 months

Temperament Traits

CourageousDignifiedGood-naturedAffectionateProtectiveCalm

Growth & Height Benchmarks

Expected Adult Weight

120-230lbs

Typical Male

120-230 lbs

30" tall

Typical Female

120-230 lbs

27.5" tall

How the Mastiff Calculator Works

1

High-Sensitivity Dynamic Modeling

We use a proprietary High-Sensitivity Dynamic Model calibrated specifically for Mastiff 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 Mastiff 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 Mastiff breed standard (120–230 lbs). While estimates can begin at 6 weeks, data collected after the 12-week mark provides the highest statistical confidence.

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