QR Code Generator

QR codes use Reed-Solomon error correction. The level you choose determines what percentage of the code can be damaged or obscured while still being readable. Higher correction = larger code for the same payload (more redundant data), so there is a tradeoff between robustness and density.

• L (Low) ~ 7% recovery — fine for digital displays where the code is rendered cleanly
• M (Medium) ~ 15% recovery — default for most printed materials
• Q (Quartile) ~ 25% recovery — outdoor signage, packaging that may wrinkle
• H (High) ~ 30% recovery — required when overlaying a logo in the center of the code (the logo obscures cells)

The "you can put your logo in the middle" trick relies entirely on H-level error correction. Without it, covering ~20% of the code corrupts data beyond recovery and the QR fails to scan.

Phones recognize special payload formats and offer one-tap actions. A Wi-Fi credentials QR uses this exact string format:

WIFI:T:WPA;S:NetworkName;P:MyPassword;;

Network: HomeWiFi
Password: hunter2!
Security: WPA2

Payload: WIFI:T:WPA;S:HomeWiFi;P:hunter2!;;

When scanned, iOS shows "Join Network HomeWiFi". Android shows a similar prompt. The user does not type the password.

• URL: https://example.com — opens in browser
• Wi-Fi: WIFI:T:WPA;S:SSID;P:password;; — joins network
• vCard: BEGIN:VCARD ... END:VCARD — adds contact
• mailto: mailto:user@example.com?subject=Hi&body=Text — composes email
• tel: tel:+48123456789 — initiates call
• sms: sms:+48123456789?body=Hi — composes SMS
• geo: geo:52.2297,21.0122 — opens maps
• Plain text: anything not matching the above — phone just displays the string

• You are printing menu QR codes that link to an online menu and want to test how small you can shrink them without losing readability.
• You are creating a Wi-Fi info card for a coffee shop or office reception so guests can join without asking for the password.
• You are putting a QR on a business card with your vCard, so a one-tap scan adds you to someone's contacts.
• You are debugging why a QR a designer mocked up does not scan — usually too-low contrast or too-small physical size for the data payload.

• It will not generate tracking-aware QR codes that count scans. That requires a redirect server (which logs each visit) — not a QR property, but a URL property.
• It will not encrypt the contents. Anyone scanning the QR sees the same data you encoded. For private payloads, encode a URL to an authenticated page instead of the secret itself.
• It will not produce print-ready vector files with bleed and crop marks. Export as SVG or high-resolution PNG and lay them out in your design tool.