If your website works on mobile data but not Wi-Fi, the site is up and the Wi-Fi path is failing. DNS, the Domain Name System that turns domain names into server addresses, is the most common cause. Router filtering and host-side IP blocking are the next suspects.
Mobile data and Wi-Fi use different networks, resolvers, and public addresses. That split helps you isolate the fault fast. Start with DNS, then check the router, then check the host.
Table of Contents
- Could Wi-Fi DNS Be the Problem?
- Is the Router Blocking the Site?
- Could Broken IPv6 Break Wi-Fi Only?
- Is the Host Blocking Your Wi-Fi Address?
- Frequently Asked Questions
Could Wi-Fi DNS Be the Problem?
Wi-Fi devices normally inherit the router's DNS resolver. Cloudflare states in its router setup guide that setting 1.1.1.1 on the router applies it to every device on that network. A wrong or filtered resolver can therefore break the site on Wi-Fi while mobile data works. Filtering is a common trap.
Cloudflare says the same router setup offers 1.1.1.2 and 1.0.0.2 to block malware. It offers 1.1.1.3 and 1.0.0.3 to block malware plus adult content across the network. That setting affects the whole Wi-Fi network at once. Google notes in its Public DNS troubleshooting guide that no responses can mean UDP and TCP DNS queries are blocked or hijacked. It directs users to test reachability with nslookup debug queries to dns.google.
- Confirm the site loads on mobile data with Wi-Fi off.
- Try one Wi-Fi device with a different public resolver and retest.
- If queries still get no response, suspect blocking or hijacking on the Wi-Fi network.
Is the Router Blocking the Site?
Home routers can block sites for Wi-Fi only. ASUS documents a Firewall > URL Filter list in its URL Filter FAQ. The black and white list accepts or rejects LAN-to-WAN URL requests in its filter table. A single entry can stop every laptop and phone on Wi-Fi. That scope matters for diagnosis.
ASUS states its routers do not support blocking a website for a specific device such as a phone or laptop. If only one Wi-Fi device fails, look at that device, not a router device rule. Open Firewall > URL Filter, Parental Controls, and security filtering on the router. Remove test entries, save, reboot, and retest the site. Ask who manages the router before changing shared settings.
Could Broken IPv6 Break Wi-Fi Only?
Another network-level cause is broken IPv6 on Wi-Fi. Dual-stack means a device can use IPv4 and IPv6. Mobile data may take a working path while Wi-Fi stalls on a bad IPv6 path. The IETF documents Happy Eyeballs Version 2 concurrency for dual-stack hosts in RFC 8305, which obsoletes RFC 6555.
For site owners, the symptom is consistent: the domain times out on Wi-Fi but loads on mobile. As a test, disable IPv6 on one Wi-Fi device or router and retest before changing hosting. Do not rebuild the site for this fault. The pattern points to transport, not content. Record which network, device, and IP version failed for the host or provider.
Is the Host Blocking Your Wi-Fi Address?
Host-side blocking can cause one-network failure. Cloudflare explains in its WAF IP Access rules documentation that IP Access rules block, challenge or allowlist traffic by visitor IP, ASN or country. Your Wi-Fi public address can be blocked while mobile data uses a different allowed address. GoDaddy directs owners to Dashboard > cPanel Admin > Security > IP Blocker to block IP addresses from an account.
Comparing the failing Wi-Fi public IP with the working mobile IP tests a host-side block. Copy both public IPs, check firewall, WAF events, and IP Blocker lists, then unblock the right address. For client sites, send both IPs and timestamps to the host. Request removal of the wrong block and retest on Wi-Fi.
Frequently Asked Questions
Will clearing WordPress cache fix Wi-Fi-only failure?
No. If mobile data already shows the current site, the site files are fine. Work through DNS, router filters, and host blocks first.
Should I change DNS on the router or one device first?
Test one device first to avoid affecting everyone on the network. Change router DNS only after the single-device test points to the resolver.
