Works on mobile data but not Wi-Fi?
Here's a pattern that trips people up constantly: a website (or app) opens instantly on your phone's mobile data, but on your home Wi-Fi it just spins or throws an error. Same phone, same site, two different results. It feels like the website is half-broken — but it almost never is. You've actually just run the cleanest diagnostic there is, and it's pointing straight at your Wi-Fi.
Why the split happens
Your phone can reach a website over two completely separate paths: your mobile carrier's network, and your home Wi-Fi (which runs through your router and internet provider). They share nothing. So when a site loads on one but not the other, you've proven two things at once:
- The website is up. It served the page fine over mobile data, so its servers are working.
- The fault is on the network that failed — here, your Wi-Fi. The problem lives somewhere between your device and the internet on that specific network.
That's the same logic our test automates: it checks the site from a neutral network and your own connection at once. When the neutral check succeeds and yours fails, it's you — exactly what "works on mobile, not Wi-Fi" already told you.
Run the test →
The usual culprits, in order
| Cause | Tell-tale sign |
|---|---|
| DNS on the router | "Server not found" for some sites while others load — the most common cause |
| Captive login page | Café / hotel / office Wi-Fi you never signed into; nothing loads until you do |
| Router needs a restart | Everything is flaky on Wi-Fi, not just one site |
| VPN or content filter | Only certain sites blocked; common on work or school networks |
| Weak signal / dropouts | Loads eventually, or only near the router |
The fix, fastest first
- Make sure you're really connected. On unfamiliar Wi-Fi, open any page — if you get a login screen, that's a captive portal; sign in and you're done.
- Restart the router. Thirty seconds unplugged. It clears a stale DNS cache and a surprising share of "some sites won't load" faults — here's why it works.
- Change your DNS. If named sites fail while everything else is fine, point your device or router at
1.1.1.1or8.8.8.8and flush the cache. This is the single highest-value fix for the mobile-works-but-Wi-Fi-doesn't pattern — full walkthrough in is it your DNS? - Check for a VPN or filter. On work, school, or guest Wi-Fi, a blocklist may be stopping just that site. Turn off any VPN and test again.
- Move closer / re-test. If it's only slow rather than blocked, weak signal may be the issue — see Wi-Fi vs. ethernet.
When it's the reverse (Wi-Fi works, mobile doesn't)
The same logic runs backwards: if a site works on Wi-Fi but not on mobile data, the fault is on the mobile side — often poor coverage where you're standing, a data cap, or your carrier's route to that service. It still isn't the website, since Wi-Fi reached it fine.