No, Virginia, There is No Such Thing as GPS Microchips (yet) Part 2 of 3

Oh, yay!  You came back for more information on GPS microchips and why they don’t exist yet.  To recap, this is a three-part series, and in part one, we dug deep into how GPS works. If you want to “skip to the end,” check out part three (although a lot of what we reference there is in part one and the post below).

Now let’s talk a bit about microchips — this will make it a bit easier to understand why technology is not quite where we need (or want) it to be to put GPS tracking inside our pets.

Microchips 101

Most pet parents are likely familiar with microchips, but in case you’re not, here goes.  Let’s start with a quick glossary of terms of the elements that are inside an animal microchip so we are all on the same page:


Looking inside a pet microchip from
  • RFID This is the type of silicon “chip” used in animal microchips. RFID stands for Radio Frequency Identification (tag). Like a UPC bar code on a box of cereal at the store that has the price and product name connected to it, RFID tags are essentially “smart” bar codes that hold a piece of unique information. RFID tags can be very small (as small as tiny cube of sea salt) and the type in animal microchips are Passive RFID and do not have an internal power source.  A passive RFID tag requires an external power source to “awaken” it so it can quickly transmit the data written on it. Think of it as someone who sleeps all the time and when poked, quickly sits up, shouts out a number and then instantly falls back asleep.
  • Tuning Capacitor The element inside the microchip that actually receives the electromagnetic power from the scanner and sends it to the RFID tag so it can “activate” to transmit data. It’s kind of like an old fashion radio turner – sound will only come out when the channel is tuned — it’s waiting to be to hear that right “channel” of radio frequency so it can “poke” the RFID chip awake so it can shout out it’s number.
  • Antenna Coil This is a teeny coil of copper inside the microchip that picks up the transmitted data from the RFID tag and helps broadcast it back to the scanner.
  • Biocompatible Material that (especially when surgically implanted) is not harmful to living tissue, i.e. means that it will be safe to put inside your pet’s body.
Cat about to be scanned for a microchip at a vet's office. Image from
Cat about to be scanned for a microchip at a vet’s office.
Image from

So in a nutshell…microchips are very small electronic RFID chips encased in a biocompatible glass cylinder that is roughly the size of a grain of rice.  This chip is surgically implanted in your pet so that it is always with them.  It’s so tiny, and they’ve done such a great job with making them biocompatible, they are widely regarded as safe and a must have for all pets.  Remember, these chips are passive – they don’t have their own source of power and can only transmit data when woken up by the surge of low-power radio waves sent out by the scanner being moved over the pet’s back, so it’s not like you’ve got some big electronic device that all sorts of things can break on inside your pet.  It’s the perfect tool for getting a lost pet home, right?  Well…sorta.

Most of you probably know that microchips as they are now are only effective if the following things go “right”:

  1. The scanner actually picks up the microchip. The RFID tags in animal microchips emit a specific radio frequency (remember that “tuning capacitor”?). So, just like when you can only hear KISS 99 FM radio when you are tuned to station number 99.1, a microchip can only be read if the scanner is looking for that type of RFID tag by sending out that specific radio frequency.  Unfortunately, there are a number of different chip frequencies out there based on the brand, and not all shelters and vets have a “universal” scanner that can read for all possible frequencies.
  2. The chip has to be registered and current. Remember, that tiny silicon chip only holds a single unique number sequence that is linked to a specific microchip account.  If the account was never registered or the information is out of date – it’s useless.
  3. The pet has actually been brought to a shelter or vet clinic to be scanned. Normal Joes and Janes don’t have a microchip scanner, so your pet might have a microchip but was never brought to a place that could scan it. Shocking as it is, there are LOTS of people who don’t even know pets might have chips in them.

Now, ALL of these things wouldn’t be an issue if we only had GPS Microchips right???  Yeah…but they don’t exist yet (really, truly, pinky-swear – as of fall 2016, they DON’T exist – so don’t believe anyone who says they do). And they probably won’t for several years to come. Based on what we’ve learned so far about GPS and microchips, there are many reason why…and I’ll map those out in part three.