Guides / How internet radio works
Explainer
How internet radio actually works
Traditional radio sends sound through the air as waves your receiver tunes into. Internet radio does the same job over the internet — and once you understand a few basic ideas, the whole thing stops feeling mysterious.
A stream is just an endless file
When you open a normal audio file, it has a beginning and an end. A radio stream is different: it is a continuous flow of audio with no end. The station's server sends out small chunks of sound one after another, and your player stitches them together as they arrive. Because it never finishes, you can't rewind or skip ahead the way you can with a podcast — you're hearing whatever the station is playing right now, the same as everyone else tuned in.
The station runs software (common examples are Icecast and SHOUTcast) that takes its live audio and broadcasts it to a web address. When your app connects to that address, it joins the broadcast already in progress.
Bitrate: the trade-off between quality and data
Bitrate measures how much data the stream uses each second, written in kilobits per second (kbps). Higher numbers mean richer sound and more data used:
- 32–64 kbps — fine for talk and news, light on data.
- 128 kbps — the everyday sweet spot for music.
- 256–320 kbps — near-CD quality, best on Wi-Fi.
If you're listening on mobile data, a lower bitrate stretches your data allowance further. On Wi-Fi, reach for the higher-quality streams.
Codecs: how the sound is packed
A codec is the method used to compress audio so it fits down an internet connection. The two you'll meet most are MP3 and AAC. AAC generally sounds a little better at the same bitrate, which is why many modern stations prefer it. You don't need to choose a codec yourself — a good player handles whatever the station sends.
Why streams buffer
Your player quietly downloads a few seconds of audio ahead of what you're hearing and keeps it in a small reserve called a buffer. If your connection hiccups, the player draws from that reserve so the music keeps going. When the reserve runs dry — a weak signal, a busy network — playback pauses to refill, and that's the "buffering" you occasionally see. A well-built app reconnects automatically when a stream drops.
Good to know: a station going quiet isn't always your fault. Stations sometimes go offline for maintenance, change their address, or hit their listener limit. That's just the nature of thousands of independent broadcasters.
Playlists: the address behind the address
Some station links don't point straight at the audio. Instead they point at a tiny playlist file (with an extension like .m3u, .pls, or .m3u8) that simply lists where the real stream lives. Your player reads the playlist, follows it to the actual audio, and starts playing. It happens in a split second, and a good app resolves these for you automatically so you never think about it.
Putting it together
So the full journey is: a station encodes its live audio with a codec at some bitrate, an Icecast or SHOUTcast server broadcasts it to a web address, your app connects (sometimes via a playlist file), buffers a few seconds, and plays. Multiply that by tens of thousands of stations worldwide and you have the entire universe of internet radio at your fingertips.