Tests what this network lets through. Nothing here changes anything — it only measures. Run it on the network you want to check.
Connection
Your public IP—
Latency (min / avg / jitter)—
Download—
Upload—
Outbound ports
UDP & VPN feasibility
UDP to video-call endpoints (Google/Cloudflare)—
Schools usually whitelist these for Meet/Zoom, so "yes" here does NOT mean a VPN will work — different destination.
UDP straight to this server, on VPN-class ports:
These stand in for VPN traffic (WireGuard uses 51820; OpenVPN-UDP 1194; IPsec/IKE 500 & 4500). Red here ⇒ an inbuilt L2TP/IPsec or WireGuard VPN just hangs at "connecting". Caveat: I can't probe 500/4500/1194 directly — the live IPsec/OpenVPN daemons own them — and a school can block 500/4500 specifically while leaving these open. The only sure test for your inbuilt VPN is a live connection while I watch the server; ask me to run that.
DNS-over-HTTPS
If these are reachable you can set encrypted DNS and the school DNS filter won't see your lookups.
Tunnels
WebSocket (WSS) out—
Most browser-based web tunnels ride on WSS over 443.
Filter fingerprint
Transparent proxy detected—
Headers the server actually received
—
via: 1.1 Caddy and the x-forwarded-* lines are added by this test server itself — ignore those. Anything else (a second IP in x-forwarded-for, x-securly, x-bluecoat-via, etc.) comes from the network.
Site reachability
Best-effort: a block page that returns "200 OK" can look reachable. Your own services (device-cert gated) may show blocked here even when they work in a real tab.