Check if a website is blocked on Wi-Fi

Six steps to find out whether your home, school or office Wi-Fi blocks a site: compare with mobile data, change DNS, check the router, use Inspect URL.

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You are on a home, school, café or office Wi-Fi, and one website will not load. Is the network blocking it on purpose, or is something simply broken? This is a six-step routine that separates the two. It needs no technical background, only a second connection such as mobile data.

Step 1. Test the same site on mobile data

Turn off Wi-Fi and open the site on mobile data. Three outcomes are possible:

  • Opens on mobile data, fails on Wi-Fi: the Wi-Fi network is involved. Continue with the steps below.
  • Fails on both: the site is probably down, or your phone has a problem. Try a public "down for everyone or just me" checker. Remember it tests from its own servers.
  • Opens on both: the issue was temporary or cached. Reload and clear the browser cache.

Note that this proves a difference between two networks. It does not prove blocking on purpose. The causes are covered in Why does a site open on mobile data but not on Wi-Fi?

Step 2. Try another device on the same Wi-Fi

Open the site on a laptop or on a friend's phone connected to the same network. If it fails everywhere on that Wi-Fi, the network or router is the cause. If it only fails on your phone, look at your phone: a VPN or proxy app, a Private DNS setting, a content-blocker, or a stale DNS cache.

Step 3. Rule out your own settings

  • Private DNS or custom DNS. Android has a "Private DNS" setting and iOS can have a DNS profile. A misconfigured one can break specific sites. Set it back to automatic and retest.
  • Another VPN, proxy or ad-blocker. Only one VPN can be active at a time on a phone. Turn each off in turn and retest.
  • Date and time. A wrong clock breaks HTTPS certificates.
  • Airplane-mode toggle and Wi-Fi reconnect. It clears stale network state, and it is worth trying before anything advanced.

Step 4. Check what the router or network says

Many routers and managed networks have a filter. Signs of a deliberate router or network filter:

  • You see an explicit page saying the site is restricted, or a redirect to a login or policy page.
  • Several sites of the same category fail together, such as social media or streaming.
  • The problem appears on every device but only on that network.

On your own home Wi-Fi, look in the router's admin page for parental controls, a "DNS filtering" feature, or a custom DNS server. On a school, café or office network you usually cannot see or change this, and it may be a policy. If you manage the network, see Which websites are blocked on my Wi-Fi? for what you can and cannot see.

Step 5. Change the DNS and retest

DNS is the most common place a network blocks or breaks a site. Switching to a different resolver is a quick test. You can set a DNS server for the Wi-Fi network in your phone's Wi-Fi settings, or let GreenTunnel use encrypted DNS for the whole device when its protection is on. If the site opens, DNS was the cause. Encrypted DNS is more reliable than plain DNS because some networks redirect plain DNS queries to their own server. More in Encrypted DNS with DoH and DoT.

Step 6. Let Inspect URL explain it

Open GreenTunnel, tap the Inspect URL tab, type the domain and tap Inspect, while connected to the Wi-Fi you are testing. The result shows two cards, Without GreenTunnel and With GreenTunnel, each with a DNS line and an HTTPS line. The one-line summary tells you which case you are in:

  • Fake DNS: the network answers with a wrong address. Encrypted DNS fixes it.
  • Name filtered: the connection is cut after the site name is read. A bypass technique may work.
  • Blocked by IP address: local techniques cannot help.
  • Works without help: not blocked on this network.

How to read every line is explained in Is a site blocked on your network? If a technique is found, tap Use this technique, turn the protection on, and check the connections in Requester.

What you can conclude, and what you cannot

  • You can conclude whether the Wi-Fi treats this site differently from mobile data, and roughly at which layer (DNS, name, address).
  • You cannot conclude who decided it or why. It may be your router's parental controls, the school's policy, or the ISP.
  • You cannot conclude that it will stay the same tomorrow. Filters change.

GreenTunnel is a local VPN with no relay server of ours, free on Android and iPhone, with optional Premium. See the home page to learn more, and How to unblock a website for the next steps.

FAQ

How can I tell if my router is blocking a site?

If the site opens on mobile data and fails on every device on the Wi-Fi, the router, its DNS or the ISP is a likely cause. Check the router admin page for parental controls or DNS filtering, or temporarily set a different DNS server and retest.

Can a Wi-Fi network see which sites I visit?

The network operator can usually see which domains you connect to, because DNS queries and the SNI field are normally visible. With HTTPS they cannot see page contents. See public Wi-Fi safety and Do I need a VPN?

Why does a site work on one Wi-Fi but not another?

Each network has its own DNS server and its own filters, and ISPs behave differently. That is why you should repeat the test whenever you change networks.

Sources

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