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I am thinking of updating a package in my app specifically I am updating "@types/react-router-dom": "4.3.1" to "5.0.0" but its in a giant project and I am afraid to break it.

So I was reading over the package.json file and I found the import "react-router-dom": "^4.3.1" with the ^ symbol ahead of the v number. And Im not sure what it means, so I cant be sure it wont be the cause for the app breaking when i update...

Can someone shed some light on this ^ symbol?

Drew Reese
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CourtneyJ
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    This is semantic versioning used by npm, you can read more about it here, https://docs.npmjs.com/about-semantic-versioning – Vaibhav Goyal Jun 29 '22 at 03:54

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^ means “compatible with”. So for example, if you were to run an npm update or npm install, with a package specified to a version "^4.3.1" in your package.json, the latest 4.x.x version would be installed, and not a 5.x.x version since that newer version would be potentially incompatible. There are a few special cases:

^1.2.3 is >=1.2.3 <2.0.0

^0.2.3 is >=0.2.3 <0.3.0 (0.x.x is special)

^0.0.1 is =0.0.1 (0.0.x is special)

^1.2 is >=1.2.0 <2.0.0 (like ^1.2.0)

^1 is >=1.0.0 <2.0.0

When in doubt with a package, I use a semver calculator like https://semver.npmjs.com/

Benson
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