**Knowing the weight of your horse** is important for several things, such as feeding properly, administering medications or dewormer paste, and generally tracking the health of your horse.

Unfortunately, we don’t all have access to scales big enough for a horse, so most horse owners end up using a traditional weight tape to measure their horse. While better than nothing, using a weight tape to measure your horse can be somewhat inaccurate at best. So, what’s a horse owner to do?

Try this: Using a seamstress tape, measure the length of your horse, and then around their girth, all in inches. Put those measurements in to this formula:

**(Heartgirth x heartgirth x body length) / 330 = Weight of horse**

If you have a mature horse, use that “330” number. If you have a yearling, use “301”, and if you have a weanling, use “280.” And last but certainly not least – have a pony? Use “299” to get the right weight.

To see a demonstration, watch our YouTube video on how to measure your horse without a scale:

Nutrena has horse weight tapes on their website that are super easy to read and use. It is kinda hard to find these tapes around here that are long enough and easy enough to read, but Nutrena has them and they are great!

Hi Elaine, Thanks for the kudos! We do really like our weight tapes – they have the formula printed right on them, and are in inches, so they work great for this method. If anyone is interested in ordering them, they can be found on our e-store at http://www.nutrenacompanystore.com.

Thanks ~ Gina T.

I’m trying to use the formula posted here for “weighing your horse without a scale,” but am coming out with some strange numbers, i.e.

heart girth 35″

body length 72″

Following the formula given, (35 x 35 x 72)/330 = weight, I get 267.27273. In other words, 35 multiplied by 35 multiplied by 72 divided by 330.

Obviously, something is wrong–I think this horse weighs around 1300.’ I tried it with another horse heart girth 32, body length 63 , and also got impossible results. Am I misinterpreting the formula somehow? Help!

Hi Linda, Thanks for checking in with us! I was confused for a moment as well – you are doing the math properly – but then I realized that your measurement numbers are off for the heartgirth. The heartgirth measurement needs to be all the way around his belly – not just one side. The number you gave, 35, is about half of what a typical heartgirth is, so I think that’s where the problem lies. If I do the math with your heartgirth measurement doubled to 70, then his weight comes out at 1069 lbs. Does that make sense? Please do let us know if you have any further questions! ~ Gina T.

Well explained, I was glad you showed different figures for different horses, as such I can apply it to my Miniature Horses

Three accurate equations for estimating body weight of the miniature horse by the Kentucky Equine Research staff.

http://www.miniaturehorsetalk.com/index.php?showtopic=68428

why is this formula considered better than a regular weight tape? Is it more accurate? Is a traditional weight tape created by using this formula for a mature horse? or How is a traditional tape created.

thank your

angela

Hello Angela, The traditional weight tape was created many years ago, and is based on a simple formula that estimates weight according to how big around the horses girth is. This new formula was developed by researchers at Texas A&M in 1983, and estimates weight based on girth and length measurements, resulting in a much more accurate number. It’s much like human measurements – if you have two people with the same size waist, but one is 5 feet tall and the other is 6 feet tall, they are going to weight different amounts. Including the length of the horse (or the height of the human) gives a much more accurate representation.

Thanks ~ Gina T.

What about Draft horses? What number would be used to divide the multiple of the heartgirth x 2 x length?

Hi Susan,

Great question. The same number, 330, still applies to draft horses!

Thanks ~ Gina T.

As this formula stated that; Heart girth x heart girth x body length) / 330 = Weight of horse.

My question is where did you people manipulated this figure 330 and confirmed that it is the right value for mature horse? I really need an explanation of how you got or derived this value 330?

Thanks

Peter

Hello Chiemela, Thank you for the question. A team of graduate students at Texas A&M developed this formula, including the use of the number 330 for mature adult full-size horses (and 301 for yearlings, 280 for weanlings, and 299 for ponies). While we don’t have their exact methods to give you, there were extensive calculations and trials behind the work to develop both the formula and those constant numbers to use.

Thank you ~ Roy J.

Hi, I own a pony, but he is really small… Not as small as a miniature pony at all, but still very small. Would “299” still work for him???

Thanks!!!

-Rebekah

Are these measurements to be done in inches?

Hi Gwen,

Yes, that is correct! Thanks for your question!