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You can't really do it with just PHP, which is server side only and stateless. It would take the user to do something each time you wanted to update the bar. The only way I can think of is to use Javascript to update the progress bar which is client side. If the server is needed to provide some kind of data to update the bar then you will need to use Ajax. Perhaps you need to explain what event(s) cause the progress bar to be updated.