How to Fix Your QR Code Scanning Problems

Fixing your QR code scanning problems is not always a straightforward procedure because QR codes can malfunction for many different reasons.

In this guide, we review the most common causes of QR code scanning problems, consider how you can fix them, and examine what steps you can follow to prevent them from happening proactively.


Common QR Code Scanning Problems

Figuring out how to fix any QR code scanning problems really comes down to understanding how QR codes work.

This is because, by understanding how QR codes work, you will be able to know what to look out for when troubleshooting your QR codes. 

Generally, the most common reasons for QR codes not functioning correctly include:

  • Color and contrast variations
  • Blurry or pixelated images
  • High complexity
  • QR code error correction-related issues

Color and Contrast Variations

Nowadays, many QR code generator tools allow businesses to tailor-make their QR codes so that they visually align with their brand. 

If done incorrectly, however, choosing aesthetically-pleasing colors when making your QR codes can get in the way of their functionality. 

Since the beginning of the QR code, it was designed to include black modules on a white background. This color contrast was what most QR code readers were designed to read. 

While current QR code readers can read colors other than black or white, readers should keep in mind that placing lighter modules over a darker background can occasionally lead to scannability issues. 

Similarly, even if a QR code has lighter colors over a darker background, if the contrast between the two colors isn’t large enough, some QR codes may be unable to read the data stored within it consistently. 

Tip: When customizing your QR code, ensure that you add your business’s logo and colors in a way that doesn’t detract from your QR code’s efficacy.

Blurry or Pixelated Images

Blurry or highly-pixelated QR codes can make it difficult for some QR readers to read them effectively. 

If you are having problems scanning your QR code, check that the quality of the image you are scanning is satisfactory. 

This point is important for more than just functionality. Since your QR codes will be shared and advertised publicly, they are essentially a reflection of your brand. This means that a low-quality, laggy, or glitchy QR code can make your audience view you as less professional.

High Complexity

Static QR codes store information directly within the black and white squares of the QR code itself. Therefore, if the information encoded within a QR code is too complicated, it can mean that it cannot be scanned — or it can scan but very slowly. 

If a QR code entails more information, it needs to be physically bigger because it will need to include more rows, columns, and patterns. 

Note that this is not the case with dynamic QR codes because the information is not actually stored within the barcode. Contrarily, dynamic codes include a small URL link that directs the QR scanner towards an online QR code generator. This is where the information is actually stored. 

Note: Unlike their static counterparts, dynamic QR codes can be edited even after they are printed. This can make them highly valuable for businesses that rely on printed advertising methods.

QR Code Error Correction-Related Issues

QR codes have a built-in ability to restore data to themselves if they are damaged. This is known as QR code error correction and is a mathematical formula within each static QR code. 

It works by converting a QR code into a polynomial expression that can be retrieved if the actual QR code is damaged or worn down. 

There are four levels of QR code error correction, all of which are capable of restoring varying amounts of a QR code’s original data. These include:

  • Level L: Able to restore 7% of a QR code’s information
  • Level M: Able to restore 15% of a QR code’s information
  • Level Q: Able to restore 25% of a QR code’s information
  • Level H: Able to restore 30% of a QR code’s information

Unfortunately, not all QR codes can be made with a level H error correction as they need to be significantly larger in order to hold the extra backup data. This can also mean that QR codes with a level H error correction experience longer loading times. 

If the error correction level of a QR code is too low relative to the damage experienced, it can result in that QR code not functioning properly. 

Similarly, if the error correction level is too high relative to the size of the QR code, it can mean that it is too complex and consequently too large to load quickly.

How to Avoid QR Code Scanning Problems

Generally, there are a couple of steps you can take to proactively ensure that you face as few QR code scanning problems as possible:

  • Choose the right QR code size: QR codes that are too small (i.e., less than 0.8 x 0.8 inches) can be unrecognizable to QR code readers. Similarly, a QR code that is too large can be practically difficult to scan. 
  • Test your QR code: You should test your QR codes’ effectiveness several times before publishing them. Ideally, you should test your QR codes using more than one operating system (e.g., android and iOS).

Frequently Asked Questions

How do I download QR codes?

With our QR code generator, you can download your tailor-made QR code by clicking on the “Save QR Code” button. 

This is found at the right of the screen and is available after the required fields (e.g., content, logo, etc.) have been filled in.

Why is my QR Code not working on my iPhone?

There are many reasons why a QR code may not be working correctly on your iPhone.These include:

  • Your iPhone does not run iOS 11 or above.
  • QR scanning is disabled in your iPhone camera’s settings.

Why is my QR code not working?

Your QR code could not be working correctly for various different reasons. Generally, QR code scanning problems are because of a QR code’s colors, quality, printed position, or expiry date.

Why is my QR Code not working when printed?

If your QR code is not working after you have printed it, you may want to check that you have placed it in a way that does not cover your QR code’s modules. 

Ideally, your QR codes need to be printed as high-quality images on flat surfaces.

For more information on how to correctly print a QR code, see our How to Print a QR Code guide.

What is the difference between status and dynamic QR codes?

The main difference between static and dynamic QR codes is that static QR codes cannot be changed after they have been generated. 

On the other hand, dynamic QR codes’ content and code can be reused and rearranged, meaning that they can be changed as many times as necessary with no problems.