Docker Network Inspector

What this reads

Paste the JSON that docker network inspect <name> prints — an array, even for a single network — and get back the driver, subnet, gateway, and every attached container broken out into a readable card, plus the checks below that flag the parts of a network's config most likely to be the actual reason two containers can't talk to each other.

What gets flagged

• The default bridge network. Docker's embedded DNS server, which lets containers find each other by name, only runs on user-defined networks — never on the network literally named bridge. Containers stuck there can only reach each other by IP.
• Internal networks. Internal: true means no route out to the internet or any other network — worth knowing before assuming a container's outbound requests are failing for some other reason.
• Docker Compose ownership. A com.docker.compose.project label means Compose created and manages this network — deleting it by hand is usually the wrong move; docker compose down is.
• Overlapping subnets across networks in the same paste. Docker refuses to create two local networks with an overlapping pool on one host, so seeing this usually means the networks came from two different hosts, or one is stale.

What this isn't

This reads the JSON you already have — it doesn't run docker commands itself, check whether a container can actually reach another one right now, or know anything about a host it isn't told about. For structural issues in a docker-compose.yml before you ever run it — undeclared networks, undefined depends_on references — see Docker Compose Validator.

FAQ

How do I get this output in the first place?

docker network inspect <name> for one network, or docker network inspect $(docker network ls -q) to dump every network on the host at once — paste either straight in.

Why do host and none networks always show empty containers and IPAM?

Both are expected to be empty. The host driver puts a container directly on the host's own network stack — no virtual IP to track. The none driver gives a container no networking beyond loopback, so there's nothing to list either.

Is my network data uploaded anywhere?

No — parsing happens entirely in your browser.