How to convert 3 digits color to 6 digits color in JavaScript

In this Article we will go through how to convert 3 digits color to 6 digits color only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const toFullHexColor = color => `#${(color.startsWith('#') ? color.slice(1) : color).split('').map(c => `${c}${c}`).join('')}`;

toFullHexColor('123');      // '#112233'
toFullHexColor('#123');     // '#112233'
toFullHexColor('#abc');     // '#aabbcc'