# Create an empty function

A function that does nothing and returns undefined.

Canonical: https://1loc.dev/function/create-an-empty-function/
Version: 1.0.0
Runtime: JavaScript · Node.js 22 / modern browsers
Verification: Usage lines executed in Node.js 22 and headless Chromium; no external services
Updated: 2026-10-28

## Implementation

```javascript
function noop() {}
```

## Usage

```javascript
const send = ({ onProgress = noop } = {}) => { onProgress(100); return 'sent'; };
send(); // → 'sent'
noop(); // → undefined
```

Lines marked → were executed in Node.js 22 and in headless Chromium, and each result was compared with the value shown. Lines marked e.g. are illustrative.

## Limits

- A shared noop makes a safe default callback, as in send above.
- The original’s alternative, Function(), compiles code at runtime: a Content-Security-Policy without unsafe-eval, such as this site’s, blocks it.

The function does not validate its arguments. Add checks where it receives untrusted input.

## Source and license

Original: https://github.com/phuocng/1loc/blob/14b481cf60dff1620ab1bb99a43b1f68068cdd9b/contents/create-an-empty-function.mdx
Author: Nguyen Huu Phuoc and original contributors
Contributors: jnields, naugtur
Source commit: 14b481cf60dff1620ab1bb99a43b1f68068cdd9b
Copyright (c) 2020 phuoc-ng
License: MIT — https://1loc.dev/licenses/
Maintainer: Oveyon
Modifications: Documented as a reference with executed usage lines. Original MDX retained as inert source evidence.