The only scanner worth owning is a universal one — a reader that picks up 125 kHz, 128 kHz and 134.2 kHz. Anything narrower will, sooner or later, look at a chipped animal and tell you it has no chip.
That is not a marginal risk. It is the central failure in pet recovery, and it is silent: a single-frequency scanner does not warn you it is the wrong tool. It simply returns nothing, and everyone in the room concludes the animal was never chipped.
Why frequency decides everything
Pet microchips run on one of three low frequencies. 134.2 kHz is the ISO standard used across Canada, Europe, Asia and Australia. The United States never fully moved, so 125 kHz and 128 kHz remain in wide circulation here alongside it.
One country, three incompatible frequencies, and animals crossing borders in both directions. A scanner that reads only one of the three is guessing.
What to look for
- Reads all three frequencies. Sometimes described as forward- and backward-reading. If the spec sheet does not name 125, 128 and 134.2 explicitly, assume it does not read all three.
- Good read range. Chips migrate from the implant site. A scanner with a narrow field makes you work harder to find one that has moved.
- Readable display and a memory. You will be writing down a 15-digit number, often in poor light with a frightened animal.
- Battery type. A scanner that is flat in the drawer is not a scanner.
How to scan properly
- Start between the shoulder blades, the standard implant site.
- Move slowly — a few inches per second. Sweeping fast is the most common reason a present chip is missed.
- Scan in an S pattern, then again perpendicular to the first pass.
- Then scan the whole animal. Neck, shoulders, down both sides, chest, front legs. Chips migrate, sometimes a long way.
- Take the collar off and move away from metal tables and other electronics, both of which interfere.
- If you get nothing, scan again with a different unit before recording the animal as unchipped.
Finding a number is only half of it
A scanner reads a number. It does not tell you who owns the animal. That number then has to resolve to a current registry record with a working phone number, or the scan achieved nothing.
Look the number up here once you have it.
Common questions
Can a phone scan a microchip?
No. Not iPhone, not Android, and no app does it. Reading a pet microchip requires a dedicated RFID scanner. The longer answer is here.
Where can I get a pet scanned for free?
Any veterinary practice, shelter or animal control office. Ask whether their scanner is universal.
Do I need to own one?
Most owners do not. Rescues, breeders, boarding facilities, groomers and anyone who regularly handles animals they did not arrive with should have one.
Related from Peeva
- Universal microchip scanners
- Pet microchip frequencies explained
- How to scan a dog’s microchip
- Look up a microchip number
Microchip resources
Find the registry by microchip prefix · Look up a microchip number · Universal microchip scanners · Register your pet’s microchip
