Optimizing QR Code Size: Minimum Dimensions for Reliable Scanning

Quick Response (QR) Codes have been in use since the 1990s, ever since they were created for the Japanese automotive industry by Denso Wave. Since then, restaurants, marketing teams, and entrepreneurs have leveraged QR Codes for a wide variety of use cases.

Unlike barcodes, you can customize QR Codes to fit virtually any ideal size, shape, or branded information. 

If you’re ready to use QR Codes for your campaign, it’s important to ensure the correct size for reliable scanning and a high error correction level. In this guide, we’ll explain the minimum dimensions for optimizing QR Code size. 

What is QR Code distance?

QR Code distance refers to the size of a QR Code relative to the distance from which people scan it. When designing QR Codes for print materials, it’s important to keep this aspect in mind to ensure that customers don’t have problems scanning your QR Codes

Designing your QR Code with the appropriate size enables customers to scan them from a distance. The farther away they can be scanned, the more likely you are to get more total scans.

Why you should care about minimum QR Code sizes

QR Codes need to be scannable from virtually any distance. As such, creators must make sure that QR Codes are the correct size and dimensions.

This is because:

  • Disproportionate QR Codes are difficult to scan. 

  • QR Codes with low scannability can frustrate your target audience. 

  • You’ll end up ruining a promising marketing campaign by not spending a few minutes optimizing the size of a QR Code. 

Ultimately, the only way for QR Codes to work well is for them to be scannable. Minimum and maximum distance scanning information is essential for determining how often or easily people scan Dynamic QR Codes.

Factors to consider for scanning QR Codes up close

You can easily scan QR Codes from a short distance. Unlike NFC technology, which has a radius of 4 cm (1.5 in), QR Codes have a minimum radius of 25 cm (10 in), which then scales up depending on the size of the QR Code. The only requirement is that the minimum size of a QR Code is of 2 x 2 cm (0.8 x 0.8 in), otherwise, a QR Code scanner could have trouble scanning it and reading the alphanumeric data. 

NFC vs QR Code scan radius
NFC vs. QR Code scan radius

QR Codes that users often scan at short distances include:

An example of a QR Code on a catalog that requires a short scanning distance
A QR Code on a catalog requires a short scanning distance

The key point here is that you can use all of the elements from the above list for contactless marketing and mobile payments due to QR Codes. 

Furthermore, they’re also convenient for customers because people don’t need to try to find links or a separate payment system. They can just scan the custom QR Code and automatically connect to the appropriate digital content, payment platform, or any amount of data for a call to action. 

If you plan to have customers scan your QR Codes up close, you should make sure they can access your collateral right away. For example, a catalog requires minimum scanning distance because a person can immediately grab it and scan a QR Code. 

The size needed for a short-distance QR Code scan

Although there is a minimum size for a QR Code of 2 x 2 cm (0.8 x 0.8 in), you can make QR Codes as large as you need to, provided that you use high-quality images so that the pixels don’t become too blurred. When designing a QR Code for a minimum distance scan, you have to also consider the placement. 

For example, if you use a QR Code on a print ad inside a train, you have to think about where people will scan it from. Perhaps people seated far away will want to scan the QR Code. Consequently, the QR Code needs to be large enough to adjust for these variables. As a general rule of thumb, use larger sizes to avoid losing any potential QR Code scans.

Factors to consider for scanning QR Codes from a distance

The farther away you expect QR Code scanning to occur, the larger the QR Code needs to be. If you put a QR Code on something like a billboard advertisement, the QR Code needs to be scannable from a long distance. Other types of QR Codes that people will scan from far away include:

An example of QR Code on a shop window that can be scanned from afar
Passersby can scan a QR Code on a shop window from afar with the right size

For some of these methods, people could still scan QR Codes from a short distance. But you always want to make sure you allow the maximum scan distance so that you don’t lose any potential customers.

If you are posting your QR Codes on collateral that’s moving, you should optimize for the maximum scan distance so anyone can access your codes on the go. 

The size needed for QR Code scans from afar

What size you need depends on a number of factors, including the height of what you’ll place the advertisement with the QR Code on (in other words, The higher the QR Code is from eye level, the bigger it needs to be), different angles from which people might scan it, and if you can create a high-resolution image for the QR Code pixels to be clear.

How small can QR Codes be for maximum effectiveness? 

To help you determine the size an ideal QR Code should be, the table below provides an overview of scanning distances and the approximate size QR Codes should be relative to that distance. 

A chart showing scan distance relative to QR Code size range

As mentioned above, always choose larger rather than smaller to ensure that the QR Code is readable and scannable from the maximum distance. Sizes listed always refer to an exact square shape because otherwise, your QR Code won’t function properly.

We’ve listed ranges here because you need to adapt the size and scan distance to the conditions of where the QR Code is placed. We recommend printing at least three different sizes and then comparing them to determine which meets the scan radius you’d like to achieve. 

The image below outlines a typical directional scan radius for which QR Codes should be designed. If you’d like a wider scan radius, you’ll need a bigger QR Code.

An example of directional QR Code scan radiusDirectional QR Code scan radius

How to ensure people can scan your QR Code

Other than designing your QR Code to be the appropriate size, there are three other main points to keep in mind to make sure your QR Code is crisp, clear, and readable: the quiet zone, image quality, and color contrast.

Maintain the quiet zone

The quiet zone is the space surrounding the QR Code that separates the QR Code’s pixels from the other designs. QR Codes need a quiet zone so that scanners can detect which images are QR Code pixels and which aren’t. Without the quiet zone, the QR Code may not work.

Use high-quality images

An example of a blurry QR Code that would be difficult to scan
An example of an easily scannable QR Code

Always print large, high-quality QR Code images so they are readable and scannable from a distance

We’ve mentioned image quality before, but we’ll stress it again. All your design efforts won’t amount to much if the QR Code image is too low quality to read! 

You can download our QR Codes as JPG, PNG, EPS, and SVG image files and then add them to any graphic design using a photo editing tool. Again, it’s a good idea to compare a few different images and QR Code sizes to ensure the resolution is high enough to be scanned from a distance.

It’s important to mention that the file format you use can affect the QR Code dimensions and the quality of your codes. We recommend using PNGs for physical campaigns. These files have better image quality than JPGs. 

However, you should ideally use JPGs for digital campaigns, as they are more compact than PNGs. 

Choose the appropriate color contrast

An example of incorrect color contrast in a QR Code
An example of correct color contrast in a QR Code

The left image shows inappropriate color contrast, while the right image shows the correct color contrast

Another important element of good QR Code design is using contrasting colors. This rule applies to both the background material for what’s behind the QR Code design and the design itself. In the image on the left, there’s no color contrast between the QR Code and the surrounding design. 

The quiet zone has also been removed, so there is no way for a QR Code scanner to detect this QR Code. The image on the right shows how to design color contrast correctly.

Focus on accessibility

If you want to maximize your reach, it’s important to make your QR Codes accessible to anyone. This means you should avoid placing your QR Codes in hard-to-reach or out-of-sight places. 

Instead, opt for visible places and large QR Code sizes if you’re placing our codes on moving objects. 

Generate effective, high-quality QR Codes with QR Code Generator PRO

QR Code size matters, and the idea size depends on your campaign, your target audience, and the location of your QR Codes. It’s essential to make sure you’re using the right sizes to maximize the impact of your campaign. 

Want to get started with a powerful QR Code generator? You’ve come to the right place. Sign up for a free QR Code Generator account today to start building high-quality custom QR Codes for any application! 

Robyn Albertyn

Robyn Albertyn is a content writer for Bitly from Cape Town, South Africa. She’s previously written about preventative health and wellness, and specializes in creative writing and copywriting. When she’s not writing, you’ll find her hiking up majestic mountains, or discovering the best coffee hotspots in her city. Feel free to say hi to her on LinkedIn.

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