Add a Cloudflare CNAME for your QR code domain

1. Add the CNAME at Cloudflare

Replace example.com with a domain you own. The example uses qr as the subdomain name. Choose a different unused name if qr already serves another service.

Sign in to Cloudflare, select your domain, and open DNS → Records.
Choose Add record and select CNAME as the type.
Enter qr for Name and custom.o2o.to for Target.
Set Proxy status to DNS only, shown with a gray cloud. Keep TTL on Auto, then save.

Use these steps when Cloudflare manages your DNS, regardless of where you registered the domain. If your hosting company manages Cloudflare on your behalf, use that company's DNS controls.

Type: CNAME
Name / Host: qr
Target / Value: custom.o2o.to
TTL: Auto
Proxy status: DNS only

The DNS name is qr; the full subdomain is qr.example.com. Enter the target as custom.o2o.to, without https:// or a path. Keep your existing root, www, and email records.

Provider reference: Cloudflare DNS instructions.

2. Connect the subdomain in your QR code account

DNS setup is only the first step. Add the same full subdomain, such as qr.example.com, in the product you use. Custom domains require a plan that includes this feature.

QR Codes Unlimited

Open Links → Domains. Enter the full subdomain without https:// or a path. Let the domain check run, then select Save Changes. If the page asks you to upgrade, choose a plan with custom domains first.

QR Code Hub for Shopify

Open Apps → QR Code Hub → Settings → Redirect Page in Shopify admin. Choose QR Code Hub as the redirect option, enter your subdomain in the custom-domain field, and use Shopify's save bar to save. The field is available on plans that include custom domains.

The CNAME setup is for the app's direct redirect option. If you use the storefront homepage or an app-generated Shopify page as the redirect page, that flow uses your storefront domain.

3. Download and scan a QR code

After saving your subdomain, open a QR code in the app and download its image. Scan that image with your phone. Check that the scan link uses your subdomain and opens the intended destination before you print it.

Changing account settings cannot rewrite a QR code that is already printed. Download an updated image to put the new domain into a code. Keep any old domain and its DNS record working while printed codes still use it.

If the domain is not working yet

Check the DNS provider. Edit records where your domain's active nameservers are managed, even if you bought the domain somewhere else.
Check the two fields. The record belongs to your subdomain; its target is custom.o2o.to. Avoid entering your QR code's destination URL as the target.
Check for an existing record. If that name is already in use, choose another unused subdomain instead of replacing a record your website needs.
Allow time for DNS caches to update. Then check the full subdomain in the app again. A save confirmation alone is not proof that the QR link works.

For this QR setup, leave the new record on DNS only (gray cloud). This avoids adding your own Cloudflare proxy in front of the QR service. See Cloudflare's explanation of proxy status.

Still stuck? Contact hello@qrcodesunlimited.com with your subdomain and a screenshot of its DNS record.