Will my QR code work forever?

A QR code encodes data statically - the image itself never expires. However, if you encoded a URL that later goes offline, the code will scan but the destination will be unavailable. For permanent use, make sure the URL is one you control long-term.

How big should a QR code be on a poster?

A common rule of thumb: the minimum print size should be at least 10× the scan distance divided by 10. For a poster viewed from 1 m away, print the code at least 10 cm × 10 cm. Higher error correction (Q or H) allows scanning even with minor damage.

What do error correction levels mean?

QR codes can recover from damage depending on the error correction level: L (7%), M (15%), Q (25%), H (30%). Higher levels make the QR code slightly larger but more resilient. Use H when adding a logo overlay.

Are Wi-Fi passwords stored anywhere?

No. All QR code generation happens entirely in your browser. Wi-Fi passwords and other sensitive data are never sent to any server.

What is the maximum amount of data a QR code can hold?

A standard QR code can hold up to 4,296 alphanumeric characters or 2,953 bytes of binary data. Very long content may require lowering the error correction level. The tool will warn you if the payload is too long.

QR Code Generator - Toolcroft

What QR codes can do

A QR code is a two-dimensional barcode that any smartphone camera can read in under a second. Unlike a URL shortener, a QR code encodes data directly in the pattern of its squares; no server is involved when someone scans it. That makes QR codes ideal for bridging print and digital: business cards, posters, packaging, event signage, and more.

Modern QR codes can encode plain text, hyperlinks, Wi-Fi credentials, contact cards (vCard), calendar events, SMS messages, phone numbers, geographic coordinates, and cryptocurrency addresses, each using a standardized URI scheme that devices know how to handle.

Wi-Fi QR codes: connect guests instantly

The Wi-Fi QR code format (WIFI:T:WPA;S:…;P:…;H:false;;) is supported natively on iOS 11+ and Android 10+. When a guest scans it, their phone prompts them to join the network (no typing required). Passwords are embedded in the image itself, so no server ever handles them. This tool processes everything locally in your browser.

Tip: print the QR code and laminate it for table tents, front-desk cards, or hotel room displays. Use error correction level Q or H if the code might get scratched or damp.

Error correction levels explained

QR codes can reconstruct data even when part of the pattern is obscured or damaged, thanks to Reed–Solomon error correction. There are four levels:

L (Low, 7%): smallest QR code, use only in clean digital environments.
M (Medium, 15%): the default; good for most uses.
Q (Quartile, 25%): recommended for codes that might be partially covered.
H (High, 30%): use when adding a logo overlay or printing in tough environments.

Higher error correction slightly increases the density (more squares), which makes the code a little harder to scan at very small sizes. Download a test PNG, then scan it with a real device before going to print.

Data type reference

Content type	URI scheme / format
URL	`https://example.com/page`
Wi-Fi	`WIFI:T:WPA;S:NetworkName;P:Password;;`
vCard contact	`BEGIN:VCARD…END:VCARD`
SMS	`sms:+15551234567?body=Hello`
Email	`mailto:user@example.com?subject=Hi`
Phone	`tel:+15551234567`
Geo coordinates	`geo:37.7749,-122.4194`
Calendar event	`BEGIN:VCALENDAR…END:VCALENDAR`

QR code version and size

A QR code’s version (1–40) determines the size of its module grid: version 1 is a 21 × 21 grid; version 40 is a 177 × 177 grid. More data or higher error correction requires a larger version (denser grid). Long URLs and full contact cards force version 5+ which makes the code slightly harder to scan at small print sizes. Shortening URLs before encoding keeps versions lower and scanning faster.