We can get a TimeRanges object for the portions of the file that have buffered.
<!DOCTYPE html> <html> <body> <audio controls> <source src='http://java2s.com/style/demo/your.ogg' type='audio/ogg; codecs=vorbis'> <source src='http://java2s.com/style/demo/your.mp3' type='audio/mpeg'> </audio> <script> let ele = document.querySelector('audio'); //if you have a video tag // let ele = document.querySelector('video'); function log() {/*www. jav a 2 s. c o m*/ for (let i = 0; i < ele.buffered.length; i++) { console.log("Portion " + i); console.log(" Start: " + ele.buffered.start(i)); console.log(" End: " + ele.buffered.end(i)); } } </script> </body> </html>