How can I tell if my dog has a fever?

While I am NOT a veterinarian or technician. from experience working in a veterinary office, a dog's temperature generally ranges between 100-102 degrees. In order to check their temperature, you can use a regular thermometer with a small amount of lubrication (such as petroleum jelly or baby oil) on the tip, and insert it about one inch into their rectum. I would also suggest having two people, one to secure the dog and distract them (petting, talking, lightly tapping them in one spot to deter their focus) and one to hold their tail out of the way and take their temp. If their temperature is over 102, particularly, 102.5 and above, I would suggest making them an appointment with their vet for a checkup to find the source of the fever.