isarray

npmv2.0.5

Array#isArray for older browsers

Not recommended for new projects

No — isarray should not be adopted for new projects. Last published 2620 days ago.

AAdoption: grade A, Excellent.
174.9M downloads per week and 3 known dependents.
FMaintenance: grade F, Failing.
Last published 2620 days ago.
AWeight: grade A, Excellent.
Zero runtime dependencies, about 3.3 KB installed.
BSupply chain: grade B, Good.
This package has a single maintainer (bus factor of 1).
ALicense: grade A, Excellent.
MIT — permissive, with no copyleft found in the dependency tree.

Grades are computed deterministically from registry metadata collected by PackageGraph — downloads, dependents, publish dates, the resolved dependency tree, maintainer count, and declared licenses. No third-party scores are used.

Install cost

What you actually take on by adding isarray to a project.

Direct dependencies

Runtime packages this one declares itself.

Total installed

Distinct packages in the full runtime tree, deduplicated the way a package manager would.

3.3 KB

Install size

Unpacked size of this package plus its entire runtime tree.

—

Tree depth

Longest resolved dependency chain below this package.

Compatibility

Node.js: No constraint declared
Module format: CommonJS only
TypeScript: No bundled types
Install scripts: None

Quick start

A usage example from the isarray README.

jsFull README ↗

var isArray = require('isarray');

console.log(isArray([])); // => true
console.log(isArray({})); // => false

isarray vs the alternatives

Packages solving a similar problem in the npm ecosystem, compared on the signals that drive an adoption decision.

Package	Weekly downloads	Dependents	License	Last release
isarraythis page	174.9M	3	MIT	7 years ago
p-locate	216.9M	1	MIT	1 day ago
open	130.4M	4	MIT	1 day ago
axios	106.5M	4	MIT	1 day ago
fflate	53.5M	1	MIT	1 day ago
default-browser	52.6M	1	MIT	1 day ago

Dependencies

Declared by isarray v2.0.5. Runtime dependencies are installed with the package; dev dependencies are not.

Dev (1)

tape ~2.13.4

Used by

Popular packages that depend on isarray.

eventsnpm

Node's event emitter for all engines.

↓ 63.8M/wk◈ 2 dependents⚖ MIT

deep-equalnpm

node's assert.deepEqual algorithm

↓ 0/wk◈ 6 dependents⚖ MIT

es-get-iteratornpm

Get an iterator for any JS language value. Works robustly across all environments, all versions.

↓ 0/wk◈ 1 dependents⚖ MIT

Relationship graph

Dependencies (left) and dependents (right) of isarray.

isarray dependencies dependents

Frequently installed together

eslintnpm

An AST-based pattern checker for JavaScript.

↓ 138.4M/wk◈ 279 dependents⚖ MITTS

call-bindnpm

Robustly `.call.bind()` a function

↓ 80.7M/wk◈ 5 dependents⚖ MIT

is-argumentsnpm

Is this an arguments object? It's a harder question than you think.

↓ 38.9M/wk◈ 2 dependents⚖ MITTS

get-intrinsicnpm

Get and robustly cache all JS language-level intrinsics at first require time

↓ 0/wk◈ 8 dependents⚖ MIT

is-regexnpm

Is this value a JS regex? Works cross-realm/iframe, and despite ES6 @@toStringTag

↓ 75.1M/wk◈ 1 dependents⚖ MITTS

stop-iteration-iteratornpm

Firefox 17-26 iterators throw a StopIteration object to indicate "done". This normalizes it.

↓ 69.2M/wk◈ 1 dependents⚖ MITTS

object-isnpm

ES2015-compliant shim for Object.is - differentiates between -0 and +0

↓ 21.5M/wk◈ 1 dependents⚖ MIT

is-shared-array-buffernpm

Is this value a JS SharedArrayBuffer?

↓ 0/wk◈ 1 dependents⚖ MITTS

is-mapnpm

Is this value a JS Map? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

↓ 0/wk◈ 1 dependents⚖ MITTS

is-setnpm

Is this value a JS Set? This module works cross-realm/iframe, and despite ES6 @@toStringTag.

↓ 0/wk◈ 1 dependents⚖ MITTS

side-channelnpm

Store information about any JS value in a side channel. Uses WeakMap if available.

↓ 0/wk◈ 3 dependents⚖ MITTS

functions-have-namesnpm

Does this JS environment support the `name` property on functions?

↓ 0/wk◈ 5 dependents⚖ MIT

Release history

No releases in the last two years, typically about 287 days apart.

Recent versions of isarray
Version	Published	Size	License
2.0.5latest	7 years ago	3.3 KB	MIT
2.0.4	8 years ago	3.4 KB	MIT
2.0.3	8 years ago	3.3 KB	MIT
2.0.2	9 years ago	—	MIT
2.0.1	10 years ago	—	MIT
2.0.0	10 years ago	—	MIT
1.0.0	10 years ago	—	MIT
0.0.1	13 years ago	—	MIT
0.0.0	13 years ago	—	MIT

Overview

isarray is an npm package that array#isArray for older browsers. It is extremely widely used, with about 174.9M downloads per week and 3 known dependents in the graph. The latest version is 2.0.5, released under the MIT license.

Who should use it

Teams working in the npm ecosystem who need array#isArray for older browsers and value a battle-tested, widely-adopted solution.

When not to use it

Consider an alternative if you need to have first-class TypeScript types out of the box, or if a more actively-maintained option better fits your npm stack.

Pros

Large, well-established user base (174.9M weekly downloads).
Clear open-source license (MIT).
Lean dependency tree (1 direct dependencies).

Cons

No bundled TypeScript types (may require a separate @types package).

Auto-generated from collected registry metadata. No external claims are inferred.

Maintainers

juliangruber

Keywords

array browser isarray

Frequently asked questions

Should I use isarray?

No — isarray should not be adopted for new projects. Last published 2620 days ago.

How do I install isarray?

Run `npm install isarray` to add isarray to your npm project.

What license is isarray released under?

isarray is distributed under the MIT license.

How popular is isarray?

isarray has approximately 174,862,265 downloads per week and 3 known dependent packages.

Is isarray still maintained?

The most recent release of isarray (v2.0.5) was published 7 years ago.

Does isarray run install scripts?

No. isarray does not define preinstall, install, or postinstall scripts, so installing it does not execute publisher-supplied code.