# Is isobject ESM-only? Can you require() it?

> isobject@4.1.1 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Returns true if the value is an object and not an array or null.

Last verified Sep 9, 2026 against isobject@4.1.1.

isobject ships CommonJS only. require("isobject") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=0.10.0. import "isobject" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

It also declares a "module" field, so bundlers such as webpack, Vite and esbuild pick up an ESM build for tree-shaking.

## What to do

1. require("isobject") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=0.10.0.
2. From ES modules use the default import: import isobject from "isobject"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: types are bundled; install nothing extra.

## Facts

- Latest: 4.1.1 (Aug 21, 2026)
- Module format: CommonJS
- Last CommonJS version: 4.1.1
- TypeScript types: bundled
- Node engines: >=0.10.0
- Weekly downloads: 52.4M
- License: MIT

## Runtime test results for isobject@4.1.1

Installed and executed on Sep 9, 2026 with require("isobject") from a CommonJS file and import "isobject" from an ES module.

| Runtime | require("isobject") | import "isobject" |
|---|---|---|
| Node.js 18 | works | works |
| Node.js 20 | works | works |
| Node.js 22 | works | works |
| Node.js 24 | works | works |
| Node.js 26 | works | works |
| Bun 1.4.0 | works | works |

## How to import isobject

ES modules:

```js
import isobject from "isobject";
```

CommonJS:

```js
const isobject = require("isobject");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (12 versions; the newest 12 shown).

| Versions | Format | First published |
|---|---|---|
| 0.1.0 – 4.1.1 | CommonJS | Jun 30, 2014 |

## Frequently asked

**Is isobject ESM-only?**

isobject@4.1.1 is a CommonJS package. isobject ships CommonJS only. require("isobject") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >=0.10.0. import "isobject" also works because Node.js and Bun can import CommonJS from ES modules, but only the default export is guaranteed; named imports depend on Node's static analysis of the module.

**Can I import isobject with ES module syntax?**

Yes. import isobject from "isobject" works in Node.js and Bun because they support importing CommonJS modules. Named imports work only when Node.js can statically detect the exports.

**Does isobject work in Bun?**

Yes. import "isobject" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does isobject ship TypeScript types?**

Yes. isobject bundles its own type declarations; no @types package is needed.

## Links

- [isobject on npm](https://www.npmjs.com/package/isobject)
- [Source repository](https://github.com/jonschlinkert/isobject)
- [HTML version](https://canirequire.com/package/isobject/)
- [JSON version](https://canirequire.com/package/isobject.json)

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