# pretty-bytes [![Build Status](https://travis-ci.org/sindresorhus/pretty-bytes.svg?branch=master)](https://travis-ci.org/sindresorhus/pretty-bytes)

> Convert bytes to a human readable string: `1337` → `1.34 kB`

Useful for displaying file sizes for humans.

*Note that it uses base-10 (e.g. kilobyte).
[Read about the difference between kilobyte and kibibyte.](https://web.archive.org/web/20150324153922/https://pacoup.com/2009/05/26/kb-kb-kib-whats-up-with-that/)*


## Install

```
$ npm install pretty-bytes
```


## Usage

```js
const prettyBytes = require('pretty-bytes');

prettyBytes(1337);
//=> '1.34 kB'

prettyBytes(100);
//=> '100 B'

// Display file size differences
prettyBytes(42, {signed: true});
//=> '+42 B'

// Localized output using German locale
prettyBytes(1337, {locale: 'de'});
//=> '1,34 kB'
```


## API

### prettyBytes(input, [options])

#### input

Type: `number`

The number to format.

#### options

Type: `Object`

##### signed

Type: `boolean`<br>
Default: `false`

Include plus sign for positive numbers. If the difference is exactly zero a space character will be prepended instead for better alignment.


##### locale

Type: `boolean` `string`<br>
Default: `false` *(No localization)*

- If `true`: Localize the output using the system/browser locale.
- If `string`: Expects a [BCP 47 language tag](https://en.wikipedia.org/wiki/IETF_language_tag) (For example: `en`, `de`, …)

**Note:** Localization should generally work in browsers. Node.js needs to be [built](https://github.com/nodejs/node/wiki/Intl) with `full-icu` or `system-icu`. Alternatively, the [`full-icu`](https://github.com/unicode-org/full-icu-npm) module can be used to provide support at runtime.


## Related

- [pretty-bytes-cli](https://github.com/sindresorhus/pretty-bytes-cli) - CLI for this module


## License

MIT © [Sindre Sorhus](https://sindresorhus.com)


Convert bytes to a human readable string: 1337 → 1.34 kB. 

@layflags/pretty-bytes

Convert bytes to a human readable string: 1337 → 1.34 kB

layflags

pretty-bytes

(Experimental) An ambiguous license classifier was found.

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Ambiguous License Classifier

Source files are encoded using a non-standard text encoding.

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Bad text encoding

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Bad semver

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Bad dependency semver

Source files contain bidirectional unicode control characters. This could indicate a Trojan source supply chain attack. See: trojansource.codes for more information.

What are bidirectional unicode control characters?

Bidirectional unicode control characters

This package has multiple bin scripts with the same name. This can cause non-deterministic behavior when installing or could be a sign of a supply chain attack.

What is bin script confusion?

Bin script confusion

This Chrome extension includes content scripts that execute JavaScript on specified websites.

What are Chrome extension content scripts?

Chrome Extension Content Script

This Chrome extension requests host permissions to access specific websites or domains.

What are Chrome extension host permissions?

Chrome Extension Host Permission

This Chrome extension requests permissions to access browser APIs, user data, or system features.

What are Chrome extension permissions?

Chrome Extension Permission

This Chrome extension requests wildcard host permissions that grant broad access to websites.

What are Chrome extension wildcard host permissions?

Chrome Extension Wildcard Host Permission

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

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Copyleft License

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Title

Critical CVE

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High CVE

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Debug access

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Deprecated

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Deprecated license

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Possible typosquat attack

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Dynamic require

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Empty package

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File dependency

Accesses the file system, and could potentially read sensitive data.

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Filesystem access

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Wildcard dependency

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Git dependency

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GitHub dependency

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AI-detected potential security risk

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Native code

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High entropy strings

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Unicode homoglyphs

Contains a dependency which resolves to a remote HTTP URL which could be used to inject untrusted code and reduce overall package reliability.

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HTTP dependency

Install scripts are run when the package is installed. The majority of malware in npm is hidden in install scripts.

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Install scripts

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Invalid manifest file

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Invisible chars

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License exception

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License Policy Violation

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Long strings

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Modified license exception

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What is network access?

Network access

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What is new author?

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Why is contributor and author data important?

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No bug tracker

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@layflags/pretty-bytes

pretty-bytes

Install

Usage

API

prettyBytes(input, [options])

input

options

signed

locale

License

Keywords

Related posts

@layflags/pretty-bytes

Install

Usage

API

prettyBytes(input, [options])

input

options

signed

locale

Related

License

Keywords

Related posts

Feross on Risky Business Weekly Podcast: npm’s Ongoing Supply Chain Attacks

Introducing Tier 1 Reachability: Precision CVE Triage for Enterprise Teams