Hi Frannie It is impossible to tell just from a horse's weight whether he is right or not – really he needs to be looked at. If you are concerned about his weight contact one of the feeding company's advice lines - all the big companies have them. The other thing to do is to 'condition score' your horse, which involves checking for example whether you can see his ribs, or whether there is a gutter (channel) down his back to his tail when viewed from behind. Again, feed company advice lines can help you with this, or you could even contact World Horse Welfare (former ILPH), which has a Right Weight campaign for horses. And don't forget to look in the pages of Your Horse for equine dietary advice. Hope that helps