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Minecraft Java Port Checker

Verify whether friends on the internet can reach your Java server’s TCP port, then diagnose why they cannot.

Minecraft Java port diagnosis

Test TCP 25565 or your custom Java server port from outside, then continue into local-service, forwarding and NAT checks.

Measured evidence first
Detected public IPChecking…
IP version—
Network—

The public IP shown here is detected from this browser request. External probes are restricted to that same public IP.

Can you join the Java server from your home network?
25565 is the default Minecraft Java TCP port.

This page is for Minecraft Java

Minecraft Bedrock is different. Bedrock commonly relies on UDP. This V3 engine intentionally does not claim to perform a general UDP/NAT-type test through the TCP Worker.

If Java works locally but the external TCP port is not reachable, check the forwarding target, server firewall, server bind address and WAN/public-IP relationship.