normalize-hex-color

A lightweight TypeScript utility that normalizes hex color codes by transforming short hex colors into full 6-digit format.

Installation

npm install normalize-hex-color

Usage

import { normalizeHexColor as nc } from 'normalize-hex-color';
// Basic usage
nc('1') // returns '#111111'
nc('12') // returns '#121212'
nc('1aC') // returns '#11AACC'
nc('123a') // returns '#123A12'
nc('123aB') // returns '#123AB1'
nc('123456') // returns '#123456'
// With hash prefix
nc('#a') // returns '#AAAAAA'
nc('#aB') // returns '#ABABAB'
nc('#aBc') // returns '#AABBCC'

// errors
nc('') // throws error
nc('G') // throws error
nc('#') // throws error

Test

npm test

Features

• Converts short hex colors to full 6-digit format
• Supports optional hash (#) prefix
• Case-insensitive input (output is always uppercase)
• Written in TypeScript with full type support
• Zero dependencies
• Comprehensive error handling

API

normalizeHexColor(input: string): string

Normalizes a hex color code by repeating the input to create a full 6-digit hex color.

Parameters

• input (string): A hex color code (1-6 digits) with optional hash prefix

Returns

• Returns a normalized 6-digit hex color code with hash prefix (uppercase)

Throws

• Throws an error if input is not a string
• Throws an error if input contains invalid hex characters

License

ISC © Hwanhoon Kim

Contributing

Issues and pull requests are welcome! Feel free to contribute to this project on GitHub.# normalize-hex-color