video_duration_html5.js

var video = document.getElementsByTagName('video')[0];
            //console.log(video.seekable.start(0));
            console.log(video.seekable);
            //console.log(video.played.end(0));
            var i = setInterval(function() {
                if(video.readyState > 0) {
                    var minutes = parseInt(video.duration / 60, 10);
                    var seconds = video.duration % 60;
                    console.log(minutes+':'+seconds);
                    // (Put the minutes and seconds in the display)

                    clearInterval(i);
                }
                console.log('not loaded');
            }, 200);