Dog Microchips: The Benefits of Microchips & What Owners Need to Know

What is a dog's microchip number?

The microchip (transponder) is a passive RFID device that is implanted under the dog’s skin—usually on the left side of the neck, between the shoulder blade and the ear. It contains a 15-digit number in accordance with ISO Standard 11784/11785, which is unique worldwide. Using a reader, this number can be read and assigned to the animal—provided the chip is properly registered.

The chip itself does not store any of the owner's personal information. It contains only the number. The owner's information is stored in a database—and that is precisely where the often-overlooked vulnerability lies.

Background + Scientific Context

Lord et al. (2009, Journal of the American Veterinary Medical Association, PubMed 19341389) characterized microchipped dogs in animal shelters: Only 58% of microchipped animals could be returned to their owners—in many cases because the chip was not registered in a database, contact information was outdated, or the reader could not detect the chip (compatibility issues). Implanting a chip is not enough—database registration is the actual goal.

Weiss et al. (2012, PubMed 22452827) analyzed North American studies on the effectiveness of animal identification: Microchipped dogs had a significantly higher return rate than unmarked animals. Owners who had registered their microchips in a database and kept their information up to date had the highest success rates.

Lord et al. (2008, Journal of the American Veterinary Medical Association, PubMed 18459918) documented methods for reuniting lost dogs with their owners: 93% of the dogs found were returned either through a direct search by the owner or after being found by a third party. Microchip databases were effective—but only if they were up to date. Incorrect or outdated owner information was the most common obstacle.

Vitomalia-Position

A microchip is the only permanently reliable way to identify dogs—unlike Collar, which can fall off, a microchip cannot be lost. However, a microchip is useless without registration in a database. We recommend: Have the microchip implanted and immediately register it in at least one searchable database—in Germany, preferably TASSO, FINDEFIX (HTV), or Petdata. If you move, change your phone number, or get a new owner: update the information immediately.

When does a dog's microchip number become important?

• Whether you're buying or adopting: Verify the microchip and database registration
• If you move or change your phone number: Update your database entry immediately
• When traveling to other EU countries: A microchip compliant with ISO 11784/11785 is required for the animal passport
• If a dog is found: helps the animal shelter or veterinarian identify the owner
• For dogs without a microchip: Starting in 2019, microchipping will be mandatory for dogs in Germany (implementing regulations of the federal states under the Animal Welfare Act)

Practical application

The chip manufacturing process, step by step:

Key databases for Germany/Austria: - TASSO e.V. (Germany): free of charge, www.tasso.net - FINDEFIX / HTV (Germany): www.findefix.com - Petdata (DE/AT): www.petdata.at - European Pet Network (Europetnet): umbrella organization, international search

Common Mistakes & Myths

• “The dog is microchipped—it always comes back.” But only if the microchip is registered in a database with up-to-date information. About 30–40% of microchipped dogs in animal shelters cannot be identified because the records are missing or out of date.
• “The chip can track the dog’s location.” A passive ISO chip is not a GPS device. It can only be read when a scanner is held directly over the chip—it does not allow for remote tracking.
• “Just implant the chip—the rest will take care of itself.” Without a database entry, the chip is worthless. Implantation and registration are two separate steps, both of which must be actively completed.

Current State of Research (2026)

ISO Standard 11784/11785 is recognized worldwide; older 9-digit chips (134.2 kHz instead of 15 digits) can cause problems in modern readers. Europetnet connects national databases across the EU—the success rate for international searches increases, but remains dependent on the completeness of national entries.

Frequently Asked Questions

Is microchipping mandatory for dogs in Germany?

In most German states, yes—under current animal welfare laws, dogs must be identified by microchip or tattoo. For international travel, the ISO microchip is the only accepted form of identification and is required (EU Pet Passport).

Where can I find my dog's microchip number?

Have the number read from your pet’s vaccination record under “Transponder/Microchip” or during your next visit to the veterinarian. The 15-digit number begins with the country code (e.g., 276 for Germany). Write it down immediately and register it in a database.

What should I do if I find a dog with a microchip?

Visit a veterinary clinic or small animal practice—every veterinarian has a scanner. Scan the microchip number and enter it into the databases (TASSO, Petdata, Europetnet). Report the find to the local animal shelter or public order office. The owner is required to take the animal back if it is found.

Related terms

• Dog Vaccination Record
• Dog Liability Insurance
• Dog license fee
• Dogs must be kept on a leash
• Animal Welfare Act: Dogs
• Traveling with a Dog

Sources & Further Reading

1. Lord, L. K., Griffin, B., Slater, M. R., & Levy, J. K. (2009). Characterization of animals with microchips entering animal shelters. Journal of the American Veterinary Medical Association, 235(2), 160–167. https://pubmed.ncbi.nlm.nih.gov/19341389/

2. Weiss, E., Slater, M., & Lord, L. (2012). Frequency of lost dogs and cats in the United States and the methods used to locate them. Animals, 2(2), 301–315. https://pubmed.ncbi.nlm.nih.gov/22452827/

3. Lord, L. K., Wittum, T. E., Ferketich, A. K., Funk, J. A., & Rajala-Schultz, P. J. (2008). Reunification of lost dogs with their owners using owner self-reports. Journal of the American Veterinary Medical Association, 232(4), 542–546. https://pubmed.ncbi.nlm.nih.gov/18459918/