Today it is possible to run most applications directly in the browser; people spend more and more time in front of a Web browser. Since audio and video communication is part of the Internet experience, major browsers are searching for ways to standardize real-time communication in Web browsers, without the need of plug-in installation. This thesis presents the possibility for real-time communication between browsers realized in JavaScript. The goal is to combine HTML5 with Mozilla audio data API for communication between browsers. To start with, the built-in media support for audio element of HTML5 has been used to embed the audio file. Extracting the samples from the audio element is done by implementing the Mozilla audio data API. These samples are compressed with a G.711 A-law codec; the codec will compress the input data by 50%. For transferring the data to the destination client and being able to receive data from the client a two-way communication channel is required. The HTML5 WebSocket API provides full-duplex communication over a single Transmission Control Protocol (TCP). The server environment chosen to support this was Node.js. All above combined together give the possibility of sending data between browsers through a server.