On gists
                Difference between pageY and clientY
                    
                        
                    
                        JavaScript
                      
                    
                    
                    
                        
                    
                    code.js
                        Raw
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                        document.addEventListener('DOMContentLoaded', _ => {
  const info = document.getElementById('info');
  const updateInfo = event => {
    const { clientX, clientY, pageX, pageY } = event;
    info.innerHTML = `clientX: ${clientX} clientY: ${clientY}<br />  pageX: ${pageX} pageY: ${pageY}`;
  };
  document.addEventListener('mouseover', updateInfo);
  document.addEventListener('mousemove', updateInfo);
});
                    
                    style.css
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                        body {
  border: 1px solid red;
  min-height: 10000px;
  margin: 10px;
}
#info {
  border: 1px solid blue;
  position: fixed;
  top: 80px;
  left: 40px;
}
                    
                    index.html
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                        <h3>Move the mouse around and scroll to see the values of clientX/Y and pageX/Y</h3>
<div id="info"></div>
                    
                    video.md
                        Raw
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