Learn what a QR code is, how QR codes work and how to use them in marketing, business and everyday life. Includes simple tips for creating your own QR codes.
QR code basics
What is a QR code? Basics, how it works and how to use QR codes
We see QR codes everywhere: on posters, menus, packages, business cards, in ads and even on invoices. Many people just scan them with their phone – but what is a QR code exactly, and how do these little black and white patterns actually work?
What is a QR code?
The term “QR code” stands for “Quick Response Code”. It is a two-dimensional barcode. Unlike a classic one-dimensional barcode, which usually encodes only numbers, a QR code can store much more information – for example:
- a website address (URL),
- contact details,
- Wi-Fi access data,
- text,
- or a calendar event.
With a single scan, users can open this information directly on their smartphone without typing anything. When someone searches for “what is qr” in a search engine, this is exactly the question they are asking: what is this code I can scan with my phone?
How does a QR code work?
A QR code consists of many small squares, the so-called modules, arranged in a square grid. Black and white areas form a pattern in which information is stored in binary form.
When you scan a QR code, the following happens in simplified form:
- The smartphone camera captures an image of the code.
- The QR code software detects typical patterns (for example the three large squares in the corners).
- The image is aligned and broken down into a grid.
- The individual modules are converted into data.
- This data is interpreted as a link, text or vCard.
Thanks to built-in error correction, QR codes can often still be read even if they are partially dirty, bent or slightly damaged.
What kind of data can a QR code store?
QR codes are very flexible and can contain different types of information. Typical examples include:
-
Website / URL
A link to a homepage, online shop or landing page. -
Contact details (vCard)
Name, company, phone number, email address and postal address – all in one contact QR code. -
Email link
An email address with pre-filled subject and body text. -
Phone number
One tap after scanning and the phone will dial the number. -
Plain text
Information, notes, instructions or coupon codes. -
Wi-Fi access data
SSID, password and encryption type, so guests can join your network quickly. -
Calendar event
An event with date, time and location.
For beginners, two types are especially important: URL QR codes (which open a website) and contact QR codes (vCard) (which save contact details directly to the address book).
How are QR codes used in everyday life?
Many users type queries like “how to use qr code” – in other words: how can I use QR codes in a meaningful way? Here are some common use cases:
Marketing & advertising
- QR code on flyers: link to a landing page with more information.
- QR code on posters: campaigns, giveaways, product pages.
- QR code in print ads: bridge from print to online offers.
Business cards & professional use
- QR code with a vCard, so contacts can save your details instantly.
- QR code with a link to your portfolio, website or LinkedIn profile.
- QR code for digital business cards on a smartphone.
Hospitality & events
- Digital menus accessed by scan.
- Reservation forms for restaurants or bars.
- Event registration or ticket purchase.
- Feedback forms after events.
Documents & invoices
- QR code linking to a support page or help center.
- Link to a download area (e.g. manuals, PDFs).
- Review links, for example to Google reviews.
In short: a QR code builds a bridge between the physical and the digital world.
How to create your own QR code
Many users search for phrases like “how to qr code” or “how make qr code”. They all want to know the same thing: how can I create my own QR code? With an online QR code generator, it’s very simple:
Step 1: Choose the QR code type
First you decide what your QR code should do. Common options include:
- URL (website, online shop, form)
- vCard (contact QR code)
- Phone number
- Text
- Wi-Fi
Step 2: Enter your content
- For URL QR codes: enter the full web address including
https://. - For a vCard: fill in fields like name, company, phone number, email and address.
- For Wi-Fi: enter the network name (SSID), password and encryption type.
Step 3: Adjust design and format
Depending on the generator, you can:
- adjust the color (a dark code on a light background is still essential),
- set the size (e.g. for business cards, flyers, posters),
- optionally add a logo (without covering important areas).
Step 4: Generate & download your QR code
One click on “Generate” – and your qrcode is created. Afterwards you can:
- download it as PNG, JPG or PDF,
- place it in your layouts (e.g. with Canva, Photoshop, InDesign, Word),
- or send it directly to an online printing service.
How to scan a QR code with your smartphone
Queries like “scan qr code online” or “scan qr code” are all about how to read QR codes in the first place. Fortunately, this is very easy today.
Scan a QR code on iPhone (iOS)
- Open the Camera app.
- Point the camera at the QR code.
- Wait briefly until a notification appears at the top.
- Tap the message, for example “Open website”.
Scan a QR code on Android smartphones
- Many devices detect QR codes directly in the default camera app.
- Alternatively, it works via Google Lens (often built into the camera or Google app).
- If necessary, you can install a dedicated QR scanner app from the app store.
Important:
- The code should be well lit.
- It should not be too small.
- It needs good contrast (dark on light background).
Security & trust when using QR codes
A QR code itself is just a “container” for data. What really matters is where it leads:
- As a user, you should ideally only scan QR codes you trust (for example from the restaurant you are sitting in, or from well-known brands).
- As a provider, you are responsible for making sure your QR codes point to serious, safe destinations – such as your own website or your official online shop.
When you use QR codes thoughtfully, they are a very convenient and safe way to provide information.
FAQ – Frequently asked questions about QR code basics
What does “QR” actually mean?
“QR” stands for “Quick Response”. The name reflects the idea that users get information quickly with a single scan.
Do I need an app to scan QR codes?
On most modern smartphones, the built-in camera app or Google Lens is enough. Only older devices still require a separate app.
Does it cost anything to create QR codes?
Many online generators are free to use. You can create as many QR codes as you like. Costs usually only arise if you want extra premium features or use a printing service.
Can I change the content of a QR code later?
With classic static QR codes, the content is permanently stored and cannot be changed afterwards. There are also dynamic QR codes where the destination can be updated in the background – but this usually requires a special service or account.
How big should a QR code be to scan reliably?
For business cards, around 2 × 2 cm is usually enough. For flyers and brochures, 2.5–3 cm is recommended. For posters or large signs, the code should be significantly bigger so it can be scanned from a distance.
Conclusion: The most important QR code basics at a glance
QR codes are a simple but very powerful tool:
- You now know what a QR code is and how it works.
- You’ve seen typical use cases in everyday life, marketing and business.
- You’ve learned how to create your own QR code and how to scan it.
With this knowledge, you are ready to use QR codes effectively in your own projects, on your website or in your business.