How to measure your dog for a Collar or Nested Prong:

For a proper fit, measure your dog's neck with a cloth seamstress's tape measure. If you do not have a tape measure, you can use a piece of string and then measure the string with a rigid ruler.
For a Regular Collar: Measure the dogs neck where you like the collar to sit. Measure your dog while standing. Not sitting, or lying down.
For a Nested Prong: For optimal results, it is recommended that our Nested Prongs be worn snugly, high up on the neck behind the ears, and under the jaw line. For a measure to sit high up on the neck as recommended, measure at this level vs lower where a normal collar would sit.
Pull the tape snug but NOT tight, and take the measure and the dog's neck. It’s best to measure more than once, to ensure it’s correct. Keep in mind that the wider the collar is made, it CAN fit a bit more snug than a narrower collar. For example, a 2.5” collar on a medium dog who normally wears 1.5” or 2” can need a lil extra room. This would be the same for a small dog who normally wears 1”. Trying a 1.5” might need a little extra room.
Round up to the nearest half inch.

For a proper fit, measure your dog's neck with a cloth seamstress's tape measure. If you do not have a tape measure, you can use a piece of string and then measure the string with a rigid ruler.