Free WiFi and Business-Card QR Codes: Choosing Colours, Logos, PNG and SVG
How to pick the error-correction level, use a centre logo, fill in the WiFi and vCard templates, and why PNG is the only download when a logo is present.
A sign in the shop that says "scan to join the WiFi", or a contact code printed on the back of a business card, saves everyone reciting a password. Here is how to configure it in TwoThink's QR Code Generator so that it still scans.
Choosing the error-correction level
- L / M: enough for short content with no logo; the modules are sparser and it looks cleaner
- Q / H: use these when you add a centre logo, or when the printed code may get scuffed
When you upload a logo, the tool raises the error correction to at least Q automatically, so the code keeps scanning.
Logo and download format
- Without a logo: PNG (you pick the side length) or SVG (a vector that stays sharp when scaled) both work
- With a logo: PNG only. Forcing a bitmap logo into an SVG makes the file large and the compatibility poor, so the SVG download is disabled outright to save you the trouble
WiFi and business-card templates
- WiFi: fill in the SSID, the password and the encryption type, and it generates a standard
WIFI:T:...string that phones can join by scanning - Business card vCard: fill in the name, phone number and email, and a scan can write them straight into the contacts
- Phone / SMS: good for a one-tap call or message on an event page
One caution: do not leave a password-bearing code on screen for long in a public place — a photo of it is the same as leaking the WiFi password.
Privacy
The code is generated locally in your browser and the contents are never uploaded, which suits internal SSIDs and personal phone numbers that you would rather not hand to an online ad network.