Quick response (QR) codes have become ubiquitous in recent years. You see them on products, advertisements, business cards, and more. QR codes make it easy to quickly open a webpage or app just by scanning the code with your smartphone camera. However, sometimes when you go to scan a QR code, it simply won’t work no matter what you try. There are several potential reasons your QR code may not be scanning properly.
The code is damaged or obscured
For a QR code to work properly, the entire code needs to be visible and intact. If part of the code is covered up, folded, scratched off, or otherwise obscured, your phone’s camera may not be able to read it accurately. Similarly, if the code is damaged or faded in any area, it can disrupt the scanning process.
Carefully inspect the QR code to make sure it is not obscured or damaged in any way. Try adjusting the angle or distance you hold your phone camera from the code. Increase or decrease ambient lighting. If it is a printed code that is damaged, try to obtain an undamaged copy of the code if possible.
The code was generated incorrectly
In order for a QR code to work correctly, it has to be properly generated to begin with. If the original QR code creator used an invalid value, set the wrong size parameters, or generated the code incorrectly, it simply won’t be readable even if perfectly printed. Most QR code generator tools and apps make it easy to create valid codes, but errors can still occur.
If the code doesn’t seem to work no matter what you try, it may be that the code itself was created incorrectly. Try having the QR code re-generated using trusted QR code software or an online generator tool. Double check all input values and settings before regenerating the code to avoid the same problem.
Your phone camera is having issues reading the code
The quality and calibration of your smartphone camera plays a big role in its ability to accurately read QR codes. An out of focus, dirty, or damaged phone camera lens could potentially have trouble clearly capturing a QR code. The camera sensor settings like white balance and exposure can also interfere with the camera properly seeing the code.
Try cleaning your phone camera lens with a microfiber cloth and make sure your hands don’t block the lens when capturing the code. Open up your camera app and point at the QR code from various distances and angles to see if you can get it to focus properly. You can also try resetting your camera app and adjusting sensor settings like exposure compensation.
The code requires an internet connection
Some QR codes are designed to open internet-based content like websites and videos. If your smartphone does not have an active internet connection via mobile data or WiFi, you may be able to scan the code but the content won’t load. The QR code itself can be read, but the result requiring an internet connection will fail.
Make sure your phone has a steady internet connection when you go to scan the QR code. Connect to a strong WiFi network or enable mobile data if you have a cellular plan. Test if you’re able to load webpages and videos before attempting the QR code scan. Also try scanning codes that don’t require internet.
The code directs to an invalid destination
A QR code is made to contain a destination like a website URL, phone number, email address, etc. to direct people to when scanned. If this destination link is broken, inactive, or incorrectly set, the QR code will scan but fail to take you anywhere useful.
Unfortunately if the destination set in the QR code itself is invalid, there is nothing you can do to get it to work properly aside from having the code re-generated with a valid value. The only exception is if the destination was previously valid and has changed, in which case informing the QR code creator to update to a working link may resolve the issue.
Your phone doesn’t have a native QR scanner
Most modern smartphones have built-in QR scanning capabilities through their camera apps. However, some older or cheaper phones may lack native support for reading QR codes through the camera directly.
If your phone did not come with a way to natively scan QR codes, you can download free scanner apps from your phone’s app store like Google Play or Apple App Store. Popular free options include QR Code Reader, QR Scanner, Kaspersky QR Scanner, and QR & Barcode Scanner. The app will use your phone’s camera to scan and interpret QR codes.
The code format is incompatible with your scanner
There are actually a few different formats of QR code with slight technical variations, though QR code readers can typically interpret all the common formats. If a very obscure or uncommon QR code format was used, your scanner may not be able to recognize it.
Standard QR codes use the ISO 18004 format. If the code you are trying to scan deviates from this format significantly, scanner apps may fail to read it properly even if the code itself has no errors. Trying a few different scanner apps may help in case one has better compatibility, but for ideal reliability stick to the most common ISO QR code format.
Your phone’s scanner app is buggy
Mobile apps can sometimes have technical issues that interfere with their proper functioning, including QR scanner apps. Bugs in the scanner software, device driver conflicts, or OS level problems could all hypothetically cause scanning difficulties.
Try force closing and reopening your QR scanner app or clearing its cache/data to reset any problematic settings. Fully close out any other open apps that could be interfering. Update your scanner app and phone OS to the newest available versions. As a last resort, uninstall and reinstall your scanner app or do a factory reset of your device if no other fixes resolve recurrent scanner issues.
The code doesn’t meet size requirements
QR code scanners need codes to be of sufficient size and clarity to accurately interpret them. Very small or low resolution QR codes may not work even if undamaged. There are minimum size requirements measured in module count rather than physical dimensions.
Standard QR code minimum size is 21 x 21 modules. If you’re having trouble scanning, try enlarging the code if possible or obtaining an alternative version that meets size requirements. Optimal size for reliable scanning is above 25 x 25 modules. Large codes are easier to scan from a distance or in less than ideal lighting.
Conclusion
QR codes provide a great way to instantly access digital information, but they won’t work properly if there are issues with the code itself or your smartphone’s scanner. Carefully inspect codes for damage or obscurity. Ensure your phone has software capable of QR scanning and a steady internet connection if needed. If problems persist, try regenerating the QR code with correct formatting and values or use an alternative scanner app. With a valid undamaged code and a properly functioning scanner, QR codes can be scanned in just a second.
Frequently Asked Questions
Why won’t my phone scan a QR code successfully?
There are several possible reasons your phone may fail to scan a QR code properly, including damage/obscurity of the code, internet connectivity issues, incompatible QR code formats, bugs in the scanner app, insufficient code size, and improper QR code generation.
How can I troubleshoot a QR code that won’t scan?
Steps to troubleshoot include cleaning the code, trying different angles/distances, checking internet connectivity, trying multiple scanner apps, resetting the scanner app, enlarging small codes, and verifying the code was generated properly without errors.
What should I do if my QR code still won’t work after troubleshooting?
If a QR code continues to fail scanning after troubleshooting cleaning, internet connectivity, app issues, etc., the code likely needs to be regenerated using a QR code generator tool to create a fresh valid code free of errors.
Can damaged QR codes be fixed?
Unfortunately physical damage to a QR code that affects the contents cannot be repaired. Obscured but intact codes may be scannable by adjusting lighting and angle. But codes with fading, scratches, or missing pieces need to be recreated without defects.
What is the ideal QR code size for easy scanning?
QR codes should be at least 21 x 21 modules in size for scanners to reliably read them. For optimal scanning reliability from any angle or distance, aim for QR code sizes above 25 x 25 modules.
Scanning Issues by QR Code Type
There are several different types of QR codes used for specific purposes. The scanning method sometimes varies based on the QR code type.
Text QR Codes
Encode plaintext letters and numbers. Readable even without an internet connection. Requires correct encoding and large enough size.
URL QR Codes
Encode web URLs to open pages in the phone’s browser. Requires internet connection. Links must be active and valid format.
Contact QR Codes
Encode contact details like phone numbers, emails, addresses. Does not require internet. Contact values must have correct formatting.
WiFi QR Codes
Encode WiFi network SSID and password to automatically connect a phone. Does not need internet but phone must support WiFi autoconnect via QR.
Payment QR Codes
Used by payment apps to encode transaction details. Requires app and account, stable internet connection.
Event QR Codes
Encode event details like dates, locations. Require calendar app support to auto-add events when scanned.
| QR Code Type | Scanning Requirements | Potential Issues |
|---|---|---|
| Text | No internet needed. Large, clean code. | Small or obscured code. Invalid text format. |
| URL | Stable internet connection. | Broken link. No internet. |
| Contact | No internet. Properly formatted details. | Incorrect contact format. Obscured code. |
| WiFi | Phone supports WiFi QR connection. | Doesn’t automatically connect phone WiFi. |
| Payment | Payment app installed. Internet connection. | App errors. Internet instability. |
| Event | Calendar app supports QR event syncing. | Details not synced to calendar. |
How to Create High Quality Scannable QR Codes
Follow these tips to generate QR codes optimized for successful scanning:
- Use a trusted QR code generator app or website to minimize errors.
- Set code size to at least 25 x 25 modules for optimal scanning.
- Choose lowest possible error correction level to reduce complexity.
- Leave a quiet zone border of at least 4 modules around the code.
- Print codes in high resolution 600dpi or higher if possible.
- Avoid folding or creasing printed code areas.
- Check code works correctly after generating and printing.
- Regenerate if any scanning issues are observed.
- Consider static cling or laminate overlays to protect printed codes.
With proper generation techniques and pristine printing quality, your custom QR codes will reliably scan every time.
Conclusion
QR codes are an ingenious way to quickly link the physical and digital worlds. However, if your QR code fails to scan properly on your smartphone, it renders the code useless. A range of factors from code damage to software bugs could be preventing successful scanning.
By methodically troubleshooting issues like obscurity, internet connectivity, app glitches, and code formatting, you can often resolve many common scanning failures. In some cases where damage or incorrect coding parameters are to blame, regeneration of the QR code may be necessary using trusted QR generator software.
With the right troubleshooting techniques and knowing what causes scanning problems in the first place, you can minimize frustration and get QR codes working reliably. When generated and implemented correctly, QR codes provide an instant bridge between offline and online environments.