Change the height of a <div> element:
document.getElementById("myDIV").style.height = "500px";
Click the button to change the height of the DIV element:
<!DOCTYPE html> <html> <head> <style> #myDIV {/*from w w w . j a v a2 s. c om*/ width: 100px; height: 100px; background-color: coral; color: white; } </style> </head> <body> <button onclick="myFunction()">Test</button> <div id="myDIV"> <h1>myDIV</h1> </div> <script> function myFunction() { document.getElementById("myDIV").style.height = "500px"; } </script> </body> </html>