Estimating your horse’s weight is very important in order to determine the exact feed ration and also to administer the right amount of treatment.
Other parameters are also important such as genetic type, breed, sex, age, stage of physiological development, duration and intensity of work, but weight is a major factor in correctly determining the feed ration.

Measurement formulas :

Height at the withers (HW) and chest measurement (CM) enable a more accurate evaluation of weight.

The precision margin is approximately 20 kg.

Body weight (BW in kg) is given by the following formulas :

Saddle horses :
Brood mare : BW (kg) = 5.2 CM + 2.6 HW - 855
Working horses : BW (kg) = 4.3 CM + 3.0 HW - 785

Draught horses :
Mares and stallions : BW (kg) = 7.3 CM - 800

For saddle horses (light and finely built horses), the weight is dependent upon the height at the withers (HW) and the chest measurement (CM), whereas for heavy horses (draught breeds), the weight is mainly dependent upon the chest measurement (CM).

Another formula with a string :

take the thoracic perimeter from the head of the withers to the girth place.

measure the distance with a meter band. Raise the measure 3 times (3th) and multiply by 80.

Concret exemple : The thoracic perimeter of you horse is : 1.85m

1.85 x 1.85 x 1.85 = 6.3316 x 80 = 506.53 kg

the error margin is + or - 20 kg