<textarea>tvoj html kod </textarea>
Skúška:
<!DOCTYPE html>
<html>
<head>
<style>
#textareaCode {
border: 1px solid #D3D3D3;
bottom: 10px;
height: 99%;
min-height: 350px;
min-width: 400px;
position: absolute;
resize: none;
top: 3px;
width: 99%;
}
</style>
</head>
<body>
<textarea id="textareaCode" cols="50" rows="10">
<!DOCTYPE html>
<html>
<body>
<h1>My First Heading</h1>
<p>My first paragraph.</p>
</body>
</html>
</textarea>
</body>
</html>