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About this tool
Explain what a caret, tilde, hyphen, x or comparator semver range actually allows, in plain English with examples.
The Semver Range Explainer desugars any npm-style semver range — caret, tilde, hyphen, x-range, comparators or || unions — into its exact comparator form and a plain-English sentence describing which versions it allows. It implements the node-semver range grammar that npm, pnpm and yarn share, so ^1.2.3 becomes >=1.2.3 <2.0.0 and ^0.2.3 becomes >=0.2.3 <0.3.0. Developers reviewing package.json entries can also test a specific version against the range and see worked allowed/blocked examples.
Open Semver Range Explainer on AltFTool — it loads instantly in your browser.
Type any npm-style range in the Version range box, or tap a preset chip such as ^1.2.3, ~1.2.3 or 1.2.x.
Read the plain-English meaning and the desugared comparators — ^1.2.3 becomes >=1.2.3 <2.0.0 — with allowed and blocked example versions.
Enter a version under 'Test a version against it' for an instant SATISFIES or does-NOT-satisfy verdict, then use Copy result.
Caret, tilde, x-range, hyphen and partial-comparator desugaring match npm's own semver library.
Every range becomes one readable sentence with explicit inclusive and exclusive bounds.
Type any concrete version and get an immediate satisfies / does-not-satisfy verdict with pre-release handling.
^1.2.3 allows every version from 1.2.3 up to but not including 2.0.0 — it freezes the left-most non-zero digit. That makes it stricter for 0.x packages: ^0.2.3 only allows up to 0.3.0 (exclusive), and ^0.0.3 allows only 0.0.3 itself.
~1.2.3 allows only patch updates (>=1.2.3 <1.3.0), while ^1.2.3 also allows minor updates (>=1.2.3 <2.0.0). For 0.2.x versions the two behave identically, because the caret then freezes the minor digit just as the tilde does.
Usually not. Under node-semver rules a pre-release version only satisfies a range that explicitly includes a pre-release tag on the same major.minor.patch — so 2.0.0-beta.1 does not match ^1.2.3 or even >=1.0.0, but 1.2.3-beta.2 does match >=1.2.3-beta.1. This prevents npm from silently installing unstable builds.
It means >=1.2.3 <2.4.0. The left side is inclusive, and a partial right side is rounded up: '- 2.3' becomes anything below 2.4.0 and '- 2' becomes anything below 3.0.0, while a full right side like '- 2.3.4' is inclusive (<=2.3.4).