How to convert 3-digit color code to 6-digit color code using JavaScript

A guide on converting 3-digit color codes (#RGB) to 6-digit color codes (#RRGGBB) using JavaScript. This ensures consistent color representation in web pages.

In this article, we will learn how to write a JavaScript function to convert a 3-digit color code (#RGB) into a 6-digit color code (#RRGGBB). This is useful when you need to standardize color values in web applications.

JavaScript Code

function convertToSixDigitColor(color) {
    // Check if the color is in the 3-digit format
    if (color.length === 4 && color[0] === '#') {
        // Convert each component R, G, B by repeating them twice
        return "#" + color[1] + color[1] + color[2] + color[2] + color[3] + color[3];
    }
    // If it's not in 3-digit format, return the original color
    return color;
}

// Example usage
let color3Digit = "#09f";  // 3-digit color code
let color6Digit = convertToSixDigitColor(color3Digit);
console.log(color6Digit);  // Output: #0099ff

Detailed explanation:

1. function convertToSixDigitColor(color): Defines a function convertToSixDigitColor with the color code as its argument.
2. if (color.length === 4 && color[0] === '#'): Checks if the color code is in 3-digit format and starts with #.
3. return "#" + color[1] + color[1] + color[2] + color[2] + color[3] + color[3];: Converts each character (R, G, B) by repeating it twice to form a 6-digit color code.
4. return color;: Returns the original color if it's not in the 3-digit format.
5. let color3Digit = "#09f";: Example of a 3-digit color code.
6. let color6Digit = convertToSixDigitColor(color3Digit);: Converts the 3-digit color code to 6 digits.
7. console.log(color6Digit);: Logs the result to the console.

Tips:

• Validate the input color code to ensure only valid formats are processed.
• While 3-digit color codes are shorthand for simple colors, 6-digit codes provide more accurate color representation.