[](http://www.uploadify.com) # onProgress Input Type:**function** Input Format:**function(event,ID,fileObj,data) {}** Required:**optional** The **onProgress** option allows you to fire a function each time to progress of a file upload changes. The default function updates the length of the progress bar and percentage displayed. If the custom function returns **false**, the default function will not run. ### Arguments **event ** The event object. **ID **The unique identifier of the file being uploaded.**** **fileObj **An object containing details about the file that was selected. - **[name]** - The name of the file**** - **[size]** - The size in bytes of the file**** - **[creationDate]** - The date the file was created**** - **[modificationDate]** - The last date the file was modified**** - **[type]** - The file extension beginning with a '.'**** **data** An object containing details about the upload and queue. - **[percentage]** - The current percentage completed for the upload**** - **[bytesLoaded]** - The current amount of bytes uploaded**** - **[allBytesLoaded]** - The current amount of bytes loaded for all files in the queue**** - **[speed]** - The current upload speed in KB/s ### Demo Javascript Code 1. $('#file_upload').uploadify({ 1. ? 'uploader' ? ?: '/uploadify/uploadify.swf', 1. ? 'script' ? ? ?: '/uploadify/uploadify.php', 1. ? 'cancelImg' ? : '/uploadify/cancel.png', 1. ? 'folder' ? ? ?: '/uploads', 1. ? 'removeCompleted' : false, 1. ? 'onProgress' ?: function(event,ID,fileObj,data){ 1. ? ? ? var bytes = Math.round(data.bytesLoaded/1024); 1. ? ? ? $('#' + $(event.target).attr('id') + ID).find('.percentage').text(' - ' + bytes + 'KB Uploaded'); 1. ? ? ? returnfalse; 1. ? ? } 1. }); HTML Code 1. <style>.uploadifyProgress{display:none;}</style> 1. <inputtype="file"id="file_upload"name="file_upload"/> 1. <ahref="javascript:$('#file_upload').uploadifyUpload();">Upload Files</a> [Upload Files](#) [](#) Help keep Uploadify free and support the development of other excellent apps!  [home](#) ?|? [about](#) ?|? [download](#) ?|? [demos](#) ?|? [documentation](#) ?|? [faqs](#) ?|? [forums](#) ?2011 by [Reactive Apps](http://www.reactiveapps.com)