How to make a QR code

You see QR codes on menus, posters, business cards. Basically everywhere. Here's how to make your own. It takes about 30 seconds.

Steps

Put in your content. Paste a URL, type some text, or enter WiFi details. Longer content makes a denser code.
Pick your look. Use the size slider. Choose colors that work with your design. Keep contrast high so scanners can read it.
Choose error correction. Higher levels add redundancy. The code still works if part of it gets covered or damaged. The tradeoff is a busier pattern.
Generate and download. Click the button, get your code. Download as PNG or SVG.
Test it. Scan with a couple different phones before you print 500 copies. Some color combos are scannable in theory but not in practice.

What this tool does

Fast generation

The code updates as you type or move the slider. No submit-and-wait cycle.

Custom colors

Set foreground and background to anything. Just make sure there's enough contrast for scanners.

PNG and SVG export

PNG for quick use. SVG if you need to scale it for print or resize it later without losing quality.

Error correction options

Four levels from Low (7%) to High (30%). Higher levels let the code survive more damage.

Runs in your browser

Nothing gets sent to a server. Your data stays on your machine.

Where people use this

Marketing materials

Put QR codes on flyers, ads, or packaging to link people to your site. Use different codes for different campaigns if you want to track which ones actually get scanned.

Events

Generate codes for tickets, venue directions, or the WiFi password. Saves people from typing long URLs on their phones.

Classrooms

Link to worksheets, videos, or reading lists. Students scan with their phones and get the material instantly.

How QR codes actually work

QR codes are 2D barcodes. A regular barcode stores data in one direction (left to right). QR codes store it in two directions, which is why they hold more information in less space.

The basics

The grid of black and white squares is binary data. A scanner reads the pattern and decodes it. Error correction means the code includes redundant data—if part of the grid is damaged or obscured, the scanner can still figure out what it says. The highest error correction level (H) can tolerate up to 30% damage.

Versions

QR codes come in 40 sizes, from 21×21 modules to 177×177. More data means a bigger grid. This tool picks the smallest version that fits your content.

Questions people ask

What does error correction level actually change?

It adds more redundant data to the code. Higher levels (Q at 25%, H at 30%) make the code scannable even if a chunk of it is covered or torn. The downside is the pattern gets denser and harder to print small. Lower levels (L at 7%, M at 15%) make simpler codes that need to stay intact.

I changed the colors and now my phone won't scan it. What happened?

Scanners rely on contrast. If your foreground and background are too similar in brightness, the scanner can't distinguish the modules. Stick to dark-on-light or light-on-dark. A pastel green on white probably won't work, even if it looks nice.

Can I make a QR code that connects people to WiFi?

Yes. Type this into the text field: WIFI:T:WPA;S:YourNetworkName;P:YourPassword;; Change WPA to WEP or nopass depending on your network. Most phones will connect automatically when they scan it.

How much data can a QR code hold?

At the largest version (40) with Low error correction, a QR code can store 4,296 letters and numbers, or 7,089 digits, or about 2,953 bytes of binary data. With higher error correction, the capacity drops because some space goes to redundancy.