To custom-fit a cot to your dog, you can measure at the shoulder and from the tip of the nose to the base of the tail, then add 6" to 8" to each measurement. This would be the laying area of your cot. The overall size of your cot will be 1" wider and 8" longer with the 3/4" EMT or 9" longer with the 1" EMT than the laying area. Please feel free to call us toll free 877-266-3923 and we will be happy to help you get the right bed for your needs.