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

> is-callable@1.2.7 is a CommonJS package. CommonJS — require() works on every Node.js version we test.

Is this JS value callable? Works with Functions and GeneratorFunctions, despite ES6 @@toStringTag.

Last verified Sep 9, 2026 against is-callable@1.2.7.

is-callable ships CommonJS only. require("is-callable") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4. import "is-callable" 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.

## What to do

1. require("is-callable") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4.
2. From ES modules use the default import: import isCallable from "is-callable"; then destructure. Named imports only work when Node.js can statically detect the exports.
3. TypeScript: npm install -D @types/is-callable

## Facts

- Latest: 1.2.7 (Sep 23, 2022)
- Module format: CommonJS
- Last CommonJS version: 1.2.7
- TypeScript types: @types/is-callable
- Node engines: >= 0.4
- Weekly downloads: 70.8M
- License: MIT

## Runtime test results for is-callable@1.2.7

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

| Runtime | require("is-callable") | import "is-callable" |
|---|---|---|
| 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 is-callable

ES modules:

```js
import isCallable from "is-callable";
```

CommonJS:

```js
const isCallable = require("is-callable");
```

## Module format by version

Derived from the type, main and exports fields of every stable release on npm (18 versions; the newest 18 shown).

| Versions | Format | First published |
|---|---|---|
| 1.0.0 – 1.2.7 | CommonJS | Jan 29, 2015 |

## Frequently asked

**Is is-callable ESM-only?**

is-callable@1.2.7 is a CommonJS package. is-callable ships CommonJS only. require("is-callable") works on every Node.js version we test (18, 20, 22, 24 and 26) and in Bun. The package declares Node.js >= 0.4. import "is-callable" 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 is-callable with ES module syntax?**

Yes. import isCallable from "is-callable" 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 is-callable work in Bun?**

Yes. import "is-callable" loaded successfully in Bun 1.4.0 on Sep 9, 2026.

**Does is-callable ship TypeScript types?**

Not bundled. Install the community types with "npm install -D @types/is-callable".

## Links

- [is-callable on npm](https://www.npmjs.com/package/is-callable)
- [Source repository](https://github.com/inspect-js/is-callable)
- [HTML version](https://canirequire.com/package/is-callable/)
- [JSON version](https://canirequire.com/package/is-callable.json)

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