Network block checker

Is your site reachable from other countries?

DNS tampering, IP blocking or TLS-SNI (DPI) reset — we check your site from networks around the world and show whether it's reachable and how access is restricted.

Install for Firefox

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World Russia · TSPUTSPU — 'technical measures to counter threats': deep packet inspection (DPI) equipment at Russian ISPs under the 'sovereign internet' law, used to block and throttle traffic. The 'Russia' check tests reachability from networks behind TSPU.

Become a network probeTake part →

What we check

01 · DNS

DNS spoofed or empty

The ISP resolver returned a wrong IP or nothing — DNS spoofing.

02 · IP

Address unreachable

Packets don’t reach the address (but do locally) — IP block or DPI.

03 · TLS-SNI

Handshake reset by SNI

Ping works but TLS to your domain breaks — SNI filtering on DPI.

Continuous monitoring

Track availability of a site or IP from Russia and worldwide: auto-checks, alerts on blocking or downtime, SSL expiry, history and a public status page.

Set up monitoring →

Become a network probe

Checks run from real volunteer networks. Install a background probe on your own network — help measure availability more accurately and earn bonus points for checks.