Port Range Expander

Expand and collapse port lists

Firewall rules, load balancers and scanning tools often need ports written either as an explicit list or as compact ranges. This tool converts between the two. Expanding turns a mixed input like "80, 443, 8000-8003" into the full list of individual ports, while collapsing takes a long list of ports and merges consecutive runs into ranges such as 8000-8003, producing the shortest readable representation. Duplicate ports are removed and everything is sorted.

Both directions are useful: some systems require every port listed explicitly, while others accept and prefer ranges for brevity.

Why port list conversion helps

Writing firewall and security-group rules by hand is error-prone when ports are scattered or span wide ranges. Expanding a range lets you verify exactly which ports a rule covers, while collapsing a list keeps configuration compact and readable. Converting between the forms also helps when moving rules between systems that use different conventions.

Ports are validated against the valid range of 0 to 65535, so out-of-range numbers are ignored. All processing happens locally in your browser, so your port lists are never uploaded.

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• Firewall Rule Risk — Evaluate firewall rules for over-permissive exposure.