How to Create and Customize Dense, Borderless QR Codes in Python

QR codes have become a staple for fast and convenient sharing of information—whether it’s a URL, text, or contact details. Using Python, you can easily generate QR codes, customize them, and make them dense or even borderless to suit specific needs. This guide will walk you through the steps to create dense QR codes, adjust their size, and even remove the side margins.

Setting Up: What You Need to Get Started

Before diving into the code, you’ll need to install the qrcode library, along with the Pillow library for handling images:

pip install qrcode[pil]

Once installed, you’re ready to create, customize, and save QR codes as images in your preferred format.

Step 1: Basic QR Code Generation

To begin with, let’s look at a simple way to create a QR code. This QR code will contain a URL or any data you’d like to encode:

import qrcode

# Data to encode
data = "https://www.example.com"  # Replace with the data you want in the QR code

# Create a QR code instance
qr = qrcode.QRCode(
    version=1,  # Basic size of the QR code
    error_correction=qrcode.constants.ERROR_CORRECT_L,
    box_size=10,
    border=4,
)

# Add data to the QR code instance
qr.add_data(data)
qr.make(fit=True)

# Create an image of the QR code
img = qr.make_image(fill_color="black", back_color="white")

# Save the image
img.save("basic_qrcode.png")

This basic code will generate a QR code with a black-and-white design and default size. However, sometimes you may need a denser QR code that can store more information in a compact space, or even a QR code without margins. Let’s see how to do that next.

Step 2: Creating a Dense QR Code

A denser QR code can store more data in a smaller space, which is particularly useful when you need a compact code that can fit into smaller areas. To increase the QR code density, you can:

• Increase the version parameter, which controls the size and complexity.
• Use a higher error correction level, such as ERROR_CORRECT_H, which also makes the QR code denser by adding redundancy for data recovery.

Here’s how to adjust the code for a denser QR code:

# Create a denser QR code instance
qr = qrcode.QRCode(
    version=10,  # Higher version number for increased density
    error_correction=qrcode.constants.ERROR_CORRECT_H,  # Higher error correction level
    box_size=5,  # Smaller box size for a compact appearance
    border=2,  # Small border to reduce whitespace around the QR code
)

# Add data and generate the QR code
qr.add_data(data)
qr.make(fit=True)

# Generate and save the image
img = qr.make_image(fill_color="black", back_color="white")
img.save("dense_qrcode.png")

By setting version=10, you make the QR code hold more data with a higher level of error correction, which is useful if the QR code might be partially obscured or damaged.

Happy Coding !