How QR Codes Work

QR (Quick Response) codes are two-dimensional barcodes that encode data in a grid of black and white squares. Invented by Denso Wave in 1994, they can hold up to 4,296 alphanumeric characters. The three large squares in the corners are finder patterns that help scanners orient the code.

Error Correction Levels

QR codes use Reed-Solomon error correction at four levels:

  • L (Low) — recovers 7% of data
  • M (Medium) — recovers 15%
  • Q (Quartile) — recovers 25%
  • H (High) — recovers 30%

Higher error correction means the code still scans even if partially obscured — useful when adding logos to the center.

What Can You Encode?

QR codes support several data formats:

  • URLs — https://codekitlab.com
  • WiFi — WIFI:T:WPA;S:MyNetwork;P:password;;
  • Email — mailto:[email protected]
  • Phone — tel:+1234567890
  • Plain text — any string up to the size limit

Generate QR Codes Instantly

Use the QR Code Generator on CodeKitLab to create QR codes for any URL or text and download them as PNG. Need a short, memorable URL to encode? Generate clean slugs with the Slug Generator first.

Embedding in HTML

After generating your QR code as a PNG, you can embed it directly or convert it to a Base64 data URI using the Image to Base64 tool — no external file needed.

Best Practices

  • Keep URLs short — shorter data means simpler codes that scan faster
  • Test at the smallest size your users will encounter
  • Use high contrast (dark on light) for reliability
  • Add a short label below the code telling users what it does

QR codes are everywhere now — from restaurant menus to deployment URLs. Having a fast generator in your toolkit saves time every week.

QR-koder for utvecklare

QR-koder kodar data i ett rutnater av svarta och vita rutor. De stodjer URLer, WiFi, e-post och vanlig text. Skapa QR-koder direkt med QR Code Generator. Konvertera till Base64 med Image to Base64.

QR-Codes fur Entwickler

QR-Codes kodieren Daten in einem Raster aus schwarzen und weissen Quadraten. Sie unterstutzen URLs, WiFi, E-Mail und Text. Erstellen Sie QR-Codes sofort mit dem QR Code Generator. Konvertieren Sie zu Base64 mit Image to Base64.

QR Codes pour developpeurs

Les QR codes encodent des donnees dans une grille de carres noirs et blancs. Ils supportent les URLs, le WiFi, l'email et le texte. Generez des QR codes avec le QR Code Generator. Convertissez en Base64 avec Image to Base64.

Codigos QR para desarrolladores

Los codigos QR codifican datos en una cuadricula de cuadrados blancos y negros. Soportan URLs, WiFi, email y texto. Genera codigos QR con el QR Code Generator. Convierte a Base64 con Image to Base64.

رموز QR للمطورين

ترمز رموز QR البيانات في شبكة من المربعات السوداء والبيضاء. تدعم الروابط وWiFi والبريد الإلكتروني والنص. أنشئ رموز QR باستخدام QR Code Generator. حول إلى Base64 باستخدام Image to Base64.

ڈویلپرز کے لیے QR کوڈز

QR کوڈز ڈیٹا کو سیاہ اور سفید مربعوں کی گرڈ میں انکوڈ کرتے ہیں۔ یہ URLs، WiFi، ای میل اور ٹیکسٹ کو سپورٹ کرتے ہیں۔ QR Code Generator سے QR کوڈ بنائیں۔ Image to Base64 سے Base64 میں تبدیل کریں۔