The tool is contained in a single HTML file that includes the HTML, CSS, and JavaScript needed to create the word counter. The HTML file includes a text box for users to enter text, and two count displays – one for the word count and one for the character count.

The CSS styles the text box and count displays, giving the text box a border, padding, and rounded corners, and aligning the count displays to the right.

The JavaScript listens for input events on the text box, and updates the word count and character count displays as the user types. It does this by getting the text from the text box, trimming it to remove leading and trailing whitespace, splitting it into an array of words using a regular expression, and counting the length of the text. It then updates the count displays with the word count and character count.