[header] How to maintain healthy weight for a horse [title] Weigh your horse. [step] The most accurate way to determine your horse's weight is to use a scale. Obviously, though, most people don't own a set of scales designed for large livestock. 
You may be able to weigh your horse at your veterinarian's office, or you may be able to have a local feed store lend you their scales. [substeps] If you own a lot of horses, it may be worth investing in a set of horse scales.