sindresorhus / is-ip

Check if a string is an IP address

is-ip

Check if a string is an IP address

If you only need this for Node.js and don't care about browser support, you may want to use net.isIP instead. Note that it returns an integer instead of a boolean.

Install

npm install is-ip

Usage

import {isIP, isIPv4} from 'is-ip';

isIP('1:2:3:4:5:6:7:8');
//=> true

isIP('192.168.0.1');
//=> true

isIPv4('1:2:3:4:5:6:7:8');
//=> false

API

isIP(string)

Check if string is IPv6 or IPv4.

isIPv6(string)

Check if string is IPv6.

isIPv4(string)

Check if string is IPv4.

ipVersion(string)

Returns 6 if string is IPv6, 4 if string is IPv4, or undefined if string is neither.

import {ipVersion} from 'is-ip';

ipVersion('1:2:3:4:5:6:7:8');
//=> 6

ipVersion('192.168.0.1');
//=> 4

ipVersion('abc');
//=> undefined

Related

• ip-regex - Regular expression for matching IP addresses
• is-cidr - Check if a string is an IP address in CIDR notation
• cidr-regex - Regular expression for matching IP addresses in CIDR notation

is-ip's Issues

Getting warning: "Package is-ip has been ignored"

I'm getting this warning when building my React Native app:

warn Package is-ip has been ignored because it contains invalid configuration. Reason: Package subpath './package.json' is not defined by "exports" in /Users/jay/app/node_modules/is-ip/package.json

I'm using is-ip@^4.0.0

Bug browser compatibility lost with version 5.0.0

Version 4.0.0 used to work in the browser, with the new super-regex dependency, this package does not work any longer.

Add checker if ipv6 ip address is a mapped ipv4 address?

References:

• https://stackoverflow.com/a/41917677/14051308
• https://stackoverflow.com/a/35560645/14051308
• https://stackoverflow.com/a/24971575/14051308

Causes PhantomJS tests to fail

While the code works as expected, it caused our PhantomJS tests to fail with the following error:

PhantomJS 2.1.1 (Mac OS X 0.0.0) ERROR
  SyntaxError: Unexpected token 'const'

node v10.21.0 (npm v6.14.8) on Mac 10.15.6

IPv4 check not works correctly

Hi everyone,
I'm facing the following issue while using your library.

isIPv4('123.123.123.');  // --> false | OK because I expect false
isIPv4('123.123.123.1');  // --> true | OK because I expect true
isIPv4('123.123.123.12');  // --> true | OK because I expect true
isIPv4('123.123.123.123');  // --> true | OK because I expect true
isIPv4('123.123.123.1234');  // --> true | NOT OK because I expect false and I get true
isIPv4('123.123.123.12345');  // --> true | NOT OK because I expect false and I get true

I'm using the 5.0.0 version and I'm using Typescript.

Return numbers on versionless check

net.isIP and is-cidr both return numbers 4, 6 or 0 on the versionless check and it makes the API a bit more elegant to use if the user needs the IP version because instead of two function calls, they can do one.

I think it would be good if is-ip would do this too, in a semver-major release of course, even thought it will be compatible with simple boolean checks like if (isIP(ip)).

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Jest encountered an unexpected token.

I am trying to use this with React. Code works fine but Jest doesn't like it. Any help would be appreciated.

`Test suite failed to run

Jest encountered an unexpected token

Jest failed to parse a file. This happens e.g. when your code or its dependencies use non-standard JavaScript syntax, or when Jest is not configured to support such syntax.

Out of the box Jest supports Babel, which will be used to transform your files into valid JS based on your Babel configuration.

By default "node_modules" folder is ignored by transformers.

Here's what you can do:
 • If you are trying to use ECMAScript Modules, see https://jestjs.io/docs/ecmascript-modules for how to enable it.
 • If you are trying to use TypeScript, see https://jestjs.io/docs/getting-started#using-typescript
 • To have some of your "node_modules" files transformed, you can specify a custom "transformIgnorePatterns" in your config.
 • If you need a custom transformation specify a "transform" option in your config.
 • If you simply want to mock your non-JS modules (e.g. binary assets) you can stub them out with the "moduleNameMapper" config option.

You'll find more details and examples of these config options in the docs:
https://jestjs.io/docs/configuration
For information about custom transformations, see:
https://jestjs.io/docs/code-transformation

`

is ipV6 false for Localhost

Hi,
I noticed that isIp.v6() returns false for ::1 (ipV6 localhost), should I open the issue here or on the ip-regex package ?
Thanks :)

Cannot utilize require, only import.

It would be nice if the package supported the older require() standard as well as the newer import().

Caught exception:  Error [ERR_REQUIRE_ESM]: require() of ES Module {...}/node_modules/is-ip/index.js from {...}/src/apiv1.js not supported.
Instead change the require of index.js in {...}/src/apiv1.js to a dynamic import() which is available in all CommonJS modules.
    at Object.<anonymous> (/{...}/src/apiv1.js:15:14)
    at Object.<anonymous> (/{...}/index.js:48:19) {
  code: 'ERR_REQUIRE_ESM'

Current workaround for anyone with issues is to force release to 3.1.0.

Performance regression in 5.x.x

Use of the super-regex module has caused a performance regression in 5.x.x of this module.

Full info and investigation is here: ChainSafe/lodestar#4689

Is there any way a different or more efficient matcher can be used?

is IPv6 not work as expected

Hi.
Function return true for:
isIp.v6('2a00:1450:4010:c0b::5f:8080')

Even for:
isIp.v6('2a00:1450:4010:c0b::5f:8080:5555')