QR code, otherwise known as Quick Response Code, is a two-dimensional barcode capable of encoding numeric, alphanumeric, byte/binary data and even Kanji characters. QR Codes have become increasingly popular in recent years due to their ability to store large amounts of data (2953 bytes of data, to be exact) and provide a convenient way for customers to access information. For more detailed information, see our guide on what is a QR Code and the differences between a QR code and a barcode.
While generating and customising a QR code is relatively easy, comprehending sizing requirements for optimal performance can be challenging. A small QR sizing error has the potential to render the QR barcode unreadable and, therefore, useless. Our article on how QR codes work explains why.
This guide will help you understand the basics of QR code sizing; from what constitutes a valid size to how to calculate the ideal size and tips to reduce QR size. But first, let’s look at what factors affect QR code size.
What Factors Influence QR Code Size?
The size of a QR code is affected by the following factors.
- Number of characters encoded
- Used Error Correction Level (ECL)
- Type of custom designing done to code
Encoded Data String Length
The most important factor that influences the size of QR codes is the amount of data encoded in them. The greater the amount of data encoded, the bigger the QR code size will be.
A QR code is capable of encoding a maximum of 2953 bytes of data, 4296 alphanumeric characters, 7089 numeric characters, or 1817 Kanji characters (character set according to JIS X 0208).
Error Correction Level (ECL)
Error correction level is the percentage damage a QR code can withstand before becoming unreadable. There are four ECLs available, namely.
- Level L (Low) – 7%
- Level M (Medium) – 15%
- Level Q (Quartile) – 25%
- Level H (High) – 30%
Choosing a higher ECL will ensure that the QR code remains readable even after taking damage, but will also increase the size of the QR code. With each increment in the ECl, more data modules are added which contain the backed-up data; thus increasing the QR code size.
QR Code Customisation
QR codes allow users to add custom design elements such as brand logos & images, graphics, shapes, colours and more. These elements add aesthetic value and brand friendliness to the QR; however, they take up space and increase the QR code’s overall size.
QR Code Sizing
Does The Size of a QR Code Matter?
Yes, the size of a QR code does matter.
QR code size and its scannability are correlated. A larger QR code size makes it easier for barcode scanners and mobile cameras to scan, while a smaller QR code size will result in incorrect decoding or even no scan at all.
What is The Maximum Size of a QR Code?
There is no standardised maximum size for a QR code; therefore, you can keep a QR code as big as you want.
However, when increasing the size of a QR code, keep the following two points in mind.
- The QR code should fit in the scanning range of the smartphone camera and QR code scanner from a normal scanning distance.
- The QR code should not get distorted due to enlargement.
What is The Minimum Size of a QR Code?
The practical minimum QR code size is 2 cm by 2 cm (0.8 inches by 0.8 inches), excluding the quiet zone.
What is The Pixel Size of a QR Code? / QR Codes Resolution Requirements
As a general rule, the minimum pixel size of a QR code should be at least 38 × 38 pixels.
However, Triton recommends keeping the QR code’s minimum resolution to 76 x 76 pixels for the best QR code scanning performance. This is because 1 centimetre corresponds to approximately 38 pixels, and the optimal QR code size should be 2 x 2 cm, which translates to 76 by 76 pixels.
What If The QR Code is Too Small?
When a QR code is too small, it can lead to major problems, including.
- Becoming unrecognisable for mobile cameras or QR code scanners
- Incorrect decoding
- No scannability in low light conditions
- Difficult for humans to detect and scan the code if printed on a physical item
How Small Can a QR Code be Printed and Still Work?
The best QR code print size, excluding the quiet zone, is 2 cm by 2 cm (0.8 inches by 0.8 inches).
However, a QR code can still be scannable even if it is smaller than the ideal size, provided that the scanning distance (QR code distance from the scanning device) is less than 5 centimetres (1.97 inches). QRs printed on business cards, visiting cards, tickets, and other forms of paper media are great examples of small-sized QR codes.
What is The Ideal Size of a Digital QR Code?
Digital QR codes work best when sized at least 240 by 240 pixels (6.35 cm by 6.35 cm) with a minimum of 72 DPI (dots per inch) resolution.
QR Code Shape
Can QR Codes be of Different Shapes?
Yes, QR codes can be of different shapes. To make differently shaped QR codes, users must fit the square QR codes within the area of the desired shape.
Does The Shape of a QR Code Matter?
Yes, the shape of a QR code does matter, as it influences the scannability of a code.
When reshaping QR codes, always remember subtlety is the key. Always go for more regular and symmetrical shapes as they are easier to scan and identifiable by users.
The QR code should not be altered to the extent that its core features, such as finder patterns, alignment patterns and quiet zone, are disturbed. Keep in mind that the more the code deviates from its original shape, the more likely it will be difficult to scan.
Why Are QR Codes Always Square? / Does a QR Code Have to be Square?
QR codes are an ISO/IEC 18004:2015 standard. Therefore, QR codes are governed by rules and specifications which require them to be in a square shape.
Here are two other reasons why QR codes are square-shaped.
- QR codes come with position patterns: three square boxes located at the three corners (top right, top left and bottom left) of a QR code. Position pattern determines the orientation of a QR code and cannot be placed on any other corner.
- QR codes require an identical “quiet zone” at all four sides of the code, making them almost appear a square shape.
Can a QR Code be Rectangular?
Yes, QR codes can be rectangular in shape.
In fact, Denso Wave, the company that developed QR codes, has come up with two new high-density rectangular versions of the QR code, namely,
- iQR Code
- rMQR (short for Rectangular Micro QR Code) – Certified as per ISO/IEC 23941:2022 standard
QR Code Design
Is it OK to Resize a QR Code? / Can I Resize QR Codes Once They Are Generated?
Yes, you can resize a QR code once it is generated. However, resizing should be done with great care, as any change (increase or decrease) in size can distort the code, making it unrecognisable for scanning devices.
If you want to use the same QR codes on different mediums of various sizes, export the code in a vector format such as EPS, SVG, or PDF. Vector formats allow you to scale the QR code without losing quality.
Follow our QR code best practices guide for more tips and tricks to keep in mind while designing and printing QR codes.
Do QR Codes Need to Have a White Background?
No, there is no compulsion to use a white background for a QR code.
In fact, the colour of a QR code plays an important role in catching attention and making it more recognisable by users. You can use different colours to make your QR codes stand out or blend with your branding guidelines.
You must, however, ensure that there is enough contrast between the colour of your QR code and the background. As a general guideline, always use light-coloured backgrounds and dark-coloured foregrounds, not the other way around.
How Much White Space do You Need Around QR Codes? / How Much Margin Should I Keep Around a QR Code? / What is an Ideal "Quite Zone"?
The size of a “quiet zone” depends on the size of your QR code. To achieve maximum scannability success, ensure the QR code is surrounded by a “quiet zone” of around 15% of the entire QR code dimension.
For example, if the QR code dimensions are 20 cm by 20 cm (7.87 inches by 7.87 inches), then the quiet zone should be at least 3 cm (1.18 inches) on all four sides.
How to Determine The Right QR Code Size?
Consider the following factors to calculate the best QR Code size for your application.
The first and most important factor in determining the size of a QR code is the distance from which it will be scanned. The larger the scanning distance, the bigger the QR code should be.
There is a standard rule for choosing the right size for a QR code. According to the rule, the ratio of the scanning distance to the size of the QR Code should be at least 10:1. In other words; the ideal QR code minimum size is equal to the scanning distance divided by 10.
For example, if the expected scanning distance is 50 inches (127 cm), then the ideal QR code size should be at least 5 inches by 5 inches (12.7 cm by 12.7 cm) or 480 pixels, excluding the quiet zone.
Amount of Data to be Encoded
QR codes store data in the form of modules (small square and rectangular patterns that make up a QR code) which are arranged in a matrix pattern. Depending on the amount of data to be stored, more or fewer modules will be used, resulting in a bigger or smaller QR code size.
At present, there are 40 versions of QR codes (from Version 1 (21 × 21 modules) to Version 40 (177 × 177 modules)), with each version having a different module configuration for storing different amounts of data. Each increment in version number increases the number of modules by 4 per side.
The maximum data capacity of any QR Code symbol version is determined by the amount of data, character type, and error correction level.
So, to determine the ideal QR code size, you should first analyse how much data and its character type you have to encode in the code.
Design of The QR Code
The design of the QR code also plays a role in its size. Design elements such as logos, images, borders, and patterns occupy space and add to the total size of a QR code.
Therefore, when calculating the size of a QR code, consider the design elements that you are planning to include with the QR code.
How to Reduce The Size of QR Codes
Here are some tips to reduce the size of a QR code.
Use Dynamic QR Code Instead of Static QR Code
Dynamic QR codes contain a short URL (usually a web address) that redirects the user to a destination page that contains the actual information. In comparison, static QR codes contain the actual information embedded within themselves.
Since dynamic QR codes only contain a few characters (web addresses) compared to static QR codes, they have few modules and are much smaller in size.
Refer to our article on dynamic vs static QR codes to learn more about the types of QR codes.
Choose an Appropriate QR Code Error Correction Level
Error correction levels help recover data from distorted and damaged codes but occupy a significant amount of space and add to the total size of a QR code.
Therefore, it is important to choose an appropriate error correction level for your application. You should consider the environmental conditions in which the code will be used and the expected QR code damage and distortion.
If the QR code is likely to face high amounts of damage, then you should choose a higher error correction level or else a lower error correction level should be enough.
Optimise Your Design
As mentioned in the previous section, design elements such as logos and borders occupy space. So, you should optimise your design to reduce the total size of a QR code.
Try using basic patterns and colours instead of complex designs. Also, keep the logos and images small or else remove them from the design entirely to save space in a QR code.
How Do I Create a Correct-Sized QR Code?
QR codes are a public domain technology, which means they are not owned by a single person or company, and there are no license restrictions or costs associated with their use. Consequently, anyone can generate a QR code for free by using an online QR code generator or downloading and installing one of the many available desktop applications.
However, these free QR code generators provide limited functionality, and will not be able to generate a QR code that meets the size requirements of your specific applications.
Therefore, if you want to create a correctly-sized QR code with the right design and features, then we recommend using Seagull Scientific’s BarTender Software.
BarTender is the world’s top label design and printing software, enabling you to design labels with graphics, text, barcodes, and RFID tags and automate and manage the entire labelling process. BarTender software lets you create and customise different types of QR codes including.
- GS1 QR code
- iQR code
- Micro QR codes
- QR code
- GS1 digital link QR code (01)(90)
- GS1 QR code (01)(8200)
Triton is proud to be an authorised reseller of Seagull Scientific BarTender Software. We offer all four editions, namely, Starter Edition, Professional Edition, Automation Edition and Enterprise Edition, at affordable pricing. To learn more about this fantastic label printing and designing software, please visit our BarTender software page or contact us via the live chat widget.
The Bottom Line
When creating a new QR code, it’s essential to choose not only the right content but also the right size. It is always recommended to make a QR code of at least 2 cm by 2 cm in order to ensure it is readable.
We hope that this article has provided you with a deep insight into QR code image size requirements and their importance for a successful QR code campaign.
Thanks for reading!