JavaScript | WebAPI | File | File.size Property

Last Updated : 18 Jan, 2019

The file.name property is an inbuilt function of file WebAPI which gives the size of a file in bytes.

Syntax:

var size = instanceOfFile.size;

Return Value: It returns a number, containing the size of the file in bytes.

Example:

<!DOCTYPE html> 
<html> 
<head> 
    <title> 
        WebAPI File.name 
    </title> 
      
    <style> 
        #main { 
            padding: 10px; 
            width: 300px; 
            border: 1px solid black; 
            text-align:center; 
            font-size:22px; 
        } 
    </style> 
</head> 
  
<body> 
    <div id = "main"> 
          
        <div>GeeksforGeeks</div> 
        <div>file.size</div> 
          
        <input type = "file" multiple id = "file_input"
            onchange = "myGeeks(this)"> 
    </div> 
      
    <script type="text/javascript"> 
        function myGeeks(fileInput) { 
              
            // File input 
            var fileInput = document.getElementById("file_input"); 
      
            var files = fileInput.files; 
              
            for (var i = 0; i < files.length; i++) { 
                alert(files[i].name + " has a size of " 
                + files[i].size + " Bytes"); 
            } 
        } 
    </script> 
    </body> 
</html>                     