PDF417 is the barcode on the back of your driver's license that holds your license data in machine-readable form
The barcode printed on the back of your driver's license is called a PDF417 — a two-dimensional barcode format that stores the same information printed on the front of your card. When a police officer, bouncer, or retail clerk scans it with a barcode reader, they see your name, address, date of birth, license number, and expiration date without having to read the text manually.
PDF417 stands for "Portable Data File, 417" — the name refers to how the barcode is structured (17 modules wide, with 4 bars and 3 spaces in each row). It was chosen for driver's licenses because it can store a large amount of data in a small space and is difficult to forge. Every state uses the same barcode format, though the specific data encoded varies slightly by state.
The barcode itself does not contain information that is not already visible on your license. It is straightforward a faster way for businesses and law enforcement to read your information without transcription errors.
Key Takeaways
- PDF417 is a two-dimensional barcode on the back of your driver's license that encodes your name, address, date of birth, license number, and expiration date.
- Scanning the barcode produces the same information as reading the front of your license — nothing hidden or additional is stored there.
- All 50 states use PDF417 on driver's licenses, though the data layout and what is encoded varies slightly by state.
- Retailers, bars, and law enforcement use barcode scanners to read your license faster and more accurately than manual entry.
How the barcode is created and what it contains
When you renew or first receive your driver's license, your state's Department of Motor Vehicles (DMV) collects your personal information and generates the PDF417 barcode automatically. The barcode is then printed directly onto the back of your physical license card during production.
The data encoded in the barcode includes your full name, date of birth, address, driver's license number, license class (what vehicles you can drive), expiration date, and any restrictions or endorsements (such as corrective lenses required or commercial driving privileges). Some states also encode your signature or a photograph reference, though this varies.
The barcode is encrypted using your state's security standards, which makes it difficult to alter or counterfeit. If someone tries to change the printed text on your license without updating the barcode, the two will no longer match when scanned — a red flag for fraud detection.
Why businesses and law enforcement scan the barcode
Scanning a barcode is faster and more accurate than manually reading and typing your information. A retail clerk checking your age for an alcohol or tobacco purchase can scan your license in one second rather than reading six separate fields and risking a typo.
For law enforcement, a barcode scan pulls your information into their database when ready, which allows them to verify your identity, check for outstanding warrants, and confirm your license status without radio communication delays. This is especially useful during traffic stops.
Bars and nightclubs use barcode scanners to verify age and to keep records of who entered the venue — a practice required by some local regulations. The scanner confirms the license is genuine and that the person is of legal age.
Privacy and what information is actually shared when your license is scanned
When someone scans your PDF417 barcode, they receive only the information encoded in that barcode — the same details printed on the front of your license. They do not automatically gain access to your criminal history, financial records, medical information, or any other government database.
However, law enforcement can use the information from your barcode scan to look up additional records in their own systems. A police officer might scan your license and then run your name through a database to check for warrants or prior arrests. That second step is a separate action and depends on what systems that officer has permission to access.
Retail businesses and bars have no access to government databases. They see only what the barcode contains: your name, address, age, and license status. They cannot look up anything beyond that without your permission.
How to know if your barcode is being read correctly
If a business or officer scans your license and the information on their screen does not match what you know to be correct, tell them when ready. A mismatch could indicate a problem with the barcode itself, a scanner malfunction, or — rarely — an error when your license was printed.
If the barcode will not scan at all, the card may be damaged. Scratches, cracks, or fading on the back of your license can make the barcode unreadable. In this case, you can request a replacement license from your state's DMV.
If you notice that information in the barcode is wrong — for example, your address is outdated or your name is misspelled — you should update your license information with your state DMV. The barcode will be regenerated when you renew or request a replacement.
Differences between states in barcode format and content
While all states use the PDF417 format, the exact layout and data fields encoded vary. Some states include more information than others — for example, a few states encode your Social Security number in the barcode, while most do not. Some states include a digital photograph or signature reference.
This variation means that a barcode scanner designed for one state may not read a license from another state correctly, or may read it but display the fields in the wrong order. Professional scanners used by law enforcement and large retailers are usually programmed to handle all 50 states, but smaller businesses may have older equipment that works only with licenses from their home state.
If you are traveling and a business cannot scan your out-of-state license, they can still read the printed information on the front. This is not a security issue — it is straightforward a limitation of their scanner.
What to do if you are concerned about barcode security
The PDF417 barcode is a standard security feature, not a privacy risk on its own. The information it contains is already printed on your license in plain text. If you are concerned about someone scanning your license without permission, the same concern applies to someone straightforward reading the front of your card.
You can request that a business not scan your license if they offer an alternative — for example, asking them to manually verify your age by reading the printed information. However, some businesses may refuse if their procedures require a scan for record-keeping or fraud prevention.
If you believe your license has been stolen or your identity has been compromised, contact your state's DMV to report it and request a replacement. You can also place a fraud alert with the three major credit bureaus (Equifax, Experian, and TransUnion) to monitor for unauthorized accounts opened in your name.
Frequently Asked Questions
Can someone read my barcode without a scanner?
No. The PDF417 barcode is a machine-readable format designed specifically for scanners. A person cannot decode it by looking at it or photographing it without specialized software. The information is encrypted and compressed in a way that makes it unreadable to the human eye.
Does the barcode contain information that is not on the front of my license?
No. The barcode contains the same information that is printed on the front of your license — name, address, date of birth, license number, and expiration date. Nothing hidden or additional is stored in the barcode. Some states may encode slightly different fields, but nothing beyond what is visible on the card.
What happens if my barcode is damaged or will not scan?
If your barcode is scratched, cracked, or faded, it may not scan. You can still use your license — the printed information on the front is still valid. However, if a business or officer needs to scan it and cannot, you may need to request a replacement license from your state's DMV.
Is PDF417 used on any other documents besides driver's licenses?
Yes. PDF417 is used on many government and commercial documents, including state ID cards, passports, airline boarding passes, and shipping labels. It is a standard barcode format chosen because it can store a large amount of data reliably in a small space.
Can I request a license without a barcode?
No. The PDF417 barcode is a standard feature on all driver's licenses issued by U.S. states. You cannot opt out of having one printed on your license. If you have concerns about privacy, you can speak with your state's DMV about your options, but a barcode-free license is not available.