tools/what-does-1-2-3-mean-in-package-json-version-rules-you-can-try.md

What does ^1.2.3 mean in package.json? Version rules you can try

Tools · 5 min read ·

Open any package.json and you'll see versions like `^4.17.21` or `~1.2.3`. That little symbol is a rule for which updates npm may install without asking you.

Here you can type a rule, release new versions into a pretend registry, and watch which ones get picked. By the end you'll know why `^` allows new features but not breaking changes, why `0.x` versions are treated as extra risky, and what `package-lock.json` is for.

Version boxes 1.0.0 to 3.0.0 with those allowed by the rule ^1.2.3 highlighted in green

$ ls tools/

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