3 tools
Reference Tools
Lookup tables and cheat sheets for the values you can never remember and always have to check.
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Semver Range Tester
Check whether a version satisfies a range — caret, tilde, x-ranges, hyphen, AND/OR — and see the resolved comparators. For Helm/npm/image tags.
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HTTP Status Codes Reference
Searchable reference for every HTTP status code — meaning, when it fires, and how DevOps/SRE teams should treat it. 1xx through 5xx.
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Common Ports Reference
Searchable table of well-known TCP/UDP ports and the services behind them — the ports you actually meet in firewalls, security groups, and incident calls.