The start() method of the TimeRanges interface returns the time offset (in seconds) at which a specified time range begins.
start(index)indexThe range number to return the starting time for.
A number.
IndexSizeError DOMExceptionThrown if the specified index doesn't correspond to an existing range.
Given a video element with the ID "myVideo":
const v = document.getElementById("myVideo");
const buf = v.buffered;
const numRanges = buf.length;
if (buf.length === 1) {
// only one range
if (buf.start(0) === 0 && buf.end(0) === v.duration) {
// The one range starts at the beginning and ends at
// the end of the video, so the whole thing is loaded
}
}This example looks at the time ranges and looks to see if the entire video has been loaded.