How to Generate a QR Code: A Complete Guide for Every Use Case

What Is a QR Code?

A QR code (Quick Response code) is a two-dimensional barcode that encodes data as a pattern of black and white squares. Unlike a traditional barcode that stores data in one direction only, a QR code stores data both horizontally and vertically — which is why it can hold significantly more information in a smaller space.

A typical QR code can store up to 3,000 alphanumeric characters or about 7,000 numeric digits. That's enough for a long URL, a Wi-Fi password, contact information, or a short paragraph of text.

How QR Codes Work

Every QR code contains several functional regions:

Finder patterns — The three square shapes in three corners that allow a camera to detect the code's orientation and boundaries from any angle.

Alignment patterns — Small squares near the lower-right corner (present in larger codes) that help decode the code even when the image is distorted.

Timing patterns — Alternating black and white squares running between the finder patterns that help the decoder determine the grid dimensions.

Data area — The rest of the code, which stores the actual encoded content plus error correction bits.

Quiet zone — A white border around the entire code (at least 4 modules wide) required for reliable scanning.

Error Correction Levels

One of the most important choices when generating a QR code is the error correction level. QR codes can be scanned even when partially damaged, obscured, or printed poorly — but only if you've selected an appropriate error correction level.

Higher error correction means more redundant data, which means the QR code must be larger (more squares) to hold the same content. For a simple URL, Level M is the standard choice. If you want to overlay your logo on the QR code, use Level H.

What You Can Encode in a QR Code

Website URL

The most common use case. Just encode the full URL:

https://example.com/landing-page?utm_source=qr

Always include the protocol (https://). Without it, some scanners open the text in a notes app instead of a browser.

Wi-Fi Network

Encoding Wi-Fi credentials lets anyone scan and connect without typing a password. The format:

WIFI:T:WPA;S:NetworkName;P:password123;H:false;;

Fields:

• T: — Security type: WPA, WEP, or nopass
• S: — SSID (network name)
• P: — Password
• H: — Hidden network: true or false

Contact Information (vCard)

BEGIN:VCARD
VERSION:3.0
FN:Jane Smith
ORG:Acme Corp
TEL:+1-555-123-4567
EMAIL:jane@acme.com
URL:https://acme.com
END:VCARD

Email

mailto:contact@example.com?subject=Hello&body=I scanned your QR code

Phone Number

tel:+15551234567

SMS

sms:+15551234567?body=Hello%20there

Plain Text

Any text string works. Useful for sharing codes, product IDs, or short instructions.

QR Code Size Guide

The size you need depends on the scanning distance and the amount of data encoded.

Rule of thumb: the QR code should be at least 1/10 of the scanning distance. If people will scan from 1 meter away, make it at least 10 cm × 10 cm.

Module size matters more than overall size. Each small square (module) in the code needs to be at least 0.3 mm for reliable printing. A QR code with 33 × 33 modules at minimum quality needs at least 1 cm × 1 cm printed.

Choosing the Right Format for Export

PNG — Best for digital use: websites, email, presentations. Lossless compression preserves sharp edges. Use at 2× or 3× the display size for retina screens.

SVG — Best for print. Scales to any size without pixelation. If you're sending to a printer or putting on merchandise, always use SVG.

JPEG — Avoid for QR codes. JPEG's lossy compression creates artifacts around the edges of squares, which can cause scan failures.

PDF — Good for professional print production. Often includes the SVG data embedded at high resolution.

Dynamic vs Static QR Codes

Static QR codes encode the destination directly. The URL is baked into the pattern — you cannot change it later without generating a new code.

Dynamic QR codes encode a short redirect URL that points to a service that then forwards to your actual destination. This lets you:

• Change the destination without reprinting
• Track scan counts by location, date, and device
• A/B test different landing pages
• Expire or deactivate a code

For print materials (flyers, packaging, business cards), dynamic QR codes are worth the trade-off of depending on a redirect service. For digital use where you control the destination, static codes are simpler and have no single point of failure.

Design and Branding

You can customize QR codes while keeping them scannable:

Color — The dark modules can be any dark color; the light modules can be any light color. The contrast ratio must remain high. Dark on light always, never light on dark.

Logo overlay — Place a logo in the center of the QR code. Use error correction level H, and keep the logo under 30% of the total code area.

Rounded modules — Some generators allow rounding the corners of individual modules. This works fine as long as the quiet zone and finder patterns remain clear.

Background — The quiet zone (white border) must be maintained. Printing on colored paper or a texture requires testing — always verify scannability before mass printing.

Common Mistakes

No quiet zone — The white border is not decorative. Scanners need it to find the code boundaries. Leave at least 4 module widths of white space on all sides.

Too much data for the size — More content means a denser code. A dense code printed small becomes unreliable. Either reduce the data or increase the print size.

Low print quality — QR codes for print need at least 300 DPI. At 72 DPI (screen resolution), they look fine on screen but become blurry when printed.

Linking to a non-mobile-friendly page — QR codes are almost always scanned on phones. Test the landing page on mobile before publishing.

Missing UTM parameters — For marketing QR codes, add UTM tracking (?utm_source=qr&utm_campaign=flyer) so you can measure results in Google Analytics.

Testing Before Publishing

Always test your QR code with at least two different scanning apps before printing. Common options:

• iPhone Camera app (built-in)
• Google Lens
• QR & Barcode Scanner (Android)
• Scan it at various distances and angles
• Print a test copy at the intended final size

A code that scans reliably on screen may fail when printed at a small size or on textured paper.

→ Use the QR Code Generator to create QR codes for URLs, Wi-Fi, contacts, and more — with color options and instant download in PNG or SVG.

For Wi-Fi-specific QR codes with the correct WIFI: format, try the Wi-Fi QR Code Generator.