Relevant links:

• Live WebVTT Validator.
• WebVTT Standard

You can simply load the parser.js file into your HTML page and the API will become available on window. Alternatively you can install it using bower (webvtt) or npm (webvtt-parser).

This module exports classes to either through window or require()/import; the ones you are likely to need are WebVTTParser and WebVTTSerializer.

To parse a WebVTT string:

import { WebVTTParser } from 'webvtt-parser';
const parser = new WebVTTParser();
const tree = parser.parse(someVTT, 'metadata');

To serialize a WebVTT tree to string:

import { WebVTTSerializer } from 'webvtt-parser';
const seri = new WebVTTSerializer();
const tree = seri.serialize(vttTree.cues)