About this tool
QR (Quick Response) codes are standard two-dimensional matrix barcodes that render machine-readable data patterns. Using client-side generation, this tool converts custom parameter payloads—like local WiFi networks, email templates, SMS routing details, and domain links—instantly.
Error Correction & Decodability Codes
QR standard patterns utilize Reed-Solomon Error Correction algorithms to ensure accuracy even when the matrix is partially obscured or damaged. The algorithm models error checks with redundant mathematical polynomial equations:
This robust structure allows scanners to reconstruct damaged parts of the code. The matrix contains distinct alignment indicators to allow smartphones to capture, de-skew, and scan data streams from any skew or capture angle.
Frequently asked questions
Everything you need to know about QR Code Generator.
What types of data can I encode in a QR code?
QR codes can store URLs, plain text, email addresses (mailto:), phone numbers (tel:), SMS templates (smsto:), WiFi credentials (WIFI:S:…), vCard contact cards, and geographic coordinates. The tool provides templates for the most common use cases.
How much data can a single QR code hold?
A QR code can store up to 7,089 numeric characters, 4,296 alphanumeric characters, or 2,953 bytes of binary data at the lowest error-correction level. In practice, keep URLs short — longer data forces a denser (harder to scan) QR code.
What size should I export a QR code for print use?
For print, export at a minimum of 300 DPI at the intended display size. A business card QR (2cm × 2cm) needs at least 240px; a poster (10cm × 10cm) should be 1200px+. The tool offers SVG export which scales without pixelation for any print size.
Can I change the colours of my QR code?
Yes. The foreground (module) and background colours are fully customisable. Maintain a minimum contrast ratio of 4:1 between foreground and background — insufficient contrast is the primary cause of QR scan failures in printing.
What happens if the URL inside my QR code changes?
A static QR code is permanently tied to the URL encoded at creation. Changing the destination URL requires generating a new QR code. For campaigns needing redirect flexibility, use a URL shortener that supports target edits, then encode the shortener URL in the QR code.