How to Create QR Codes: Complete Guide for Developers and Marketers

What is a QR code?

QR (Quick Response) codes are two-dimensional barcodes that store data in a pattern of black and white squares. They can be scanned by smartphones to instantly access URLs, contact information, WiFi credentials, and more.

Originally invented in 1994 for tracking automotive parts, QR codes have become ubiquitous in marketing, payments, and digital interactions.

Types of QR code data

QR codes can encode various types of data, each triggering different actions when scanned.

• URL: Opens a website in the default browser
• WiFi: Connects to a network without manual password entry
• vCard: Adds a contact to the phone address book
• Email: Opens email app with pre-filled recipient and subject
• Phone: Initiates a phone call
• SMS: Opens messaging app with pre-filled number and text
• Plain text: Displays any custom text content

Error correction levels

QR codes include redundant data that allows them to be read even when partially damaged or obscured. Higher error correction makes larger codes but handles more damage.

• L (7%): Smallest code size, minimal damage recovery
• M (15%): Good balance between size and recovery
• Q (25%): Better recovery, suitable for busy environments
• H (30%): Best for printed codes that may get worn

WiFi QR codes

WiFi QR codes are incredibly useful for sharing network access. When scanned, they automatically connect the device to your network without typing the password.

They support WPA/WPA2, WEP, and open networks. You can also indicate if the network is hidden.

vCard contact QR codes

vCard QR codes contain contact information in a standardized format. When scanned, phones offer to save the contact directly to the address book.

You can include name, phone, email, company, job title, and website URL.

Best practices for QR codes

Follow these guidelines to ensure your QR codes scan reliably.

• Size matters: At least 2cm for close scanning, larger for distance
• High contrast: Dark foreground on light background works best
• Quiet zone: Keep white space around the code (at least 4 modules)
• Short content: Less data means simpler, faster-scanning codes
• Test before printing: Verify with multiple scanning apps
• Consider error correction: Use H level for printed materials

Customizing QR code colors

While traditional QR codes are black and white, you can customize colors for branding purposes. However, maintain sufficient contrast between foreground and background colors.

Avoid using colors that are too similar or low contrast, as this can make scanning unreliable. Dark colors on light backgrounds work better than the reverse.

Static vs dynamic QR codes

Static QR codes (like those generated by our tool) encode data directly in the code pattern. They never expire and work offline.

Dynamic QR codes redirect through a service URL, allowing you to change the destination after printing. However, they require an internet connection and depend on the service staying online.