Bitrate is the quantity of digital information your device processes every second when playing or recording audio. It's measured in kilobits per second (kbps) or megabits per second (Mbps). A higher bitrate means more data is devoted to capturing the nuances of sound, typically resulting in richer, more detailed audio.
Think of bitrate like the resolution of a photo. A 320 kbps MP3 file contains more audio information than a 128 kbps file of the same song. The extra data preserves more of the original recording's character, including subtle instruments, vocal texture, and dynamic range. Streaming services use variable bitrates: Spotify plays at up to 320 kbps on Premium, whilst lower-cost tiers use 96 kbps or 160 kbps.
Bitrate affects three practical things when you're choosing audio equipment or services. First, file size: a 3-minute song at 128 kbps takes roughly 2.8 MB, whilst the same track at 320 kbps uses 7 MB. Second, streaming quality: a lower bitrate means smaller downloads and faster buffering, useful on poor mobile connections. Third, audibility: most people can't hear the difference between 256 kbps and 320 kbps, but the jump from 128 kbps to 256 kbps is noticeable on decent headphones or speakers.
When buying headphones, speakers, or choosing a music streaming service, check what bitrates they support. Audiophiles often prefer lossless formats like FLAC or ALAC, which use bitrates of 1000 kbps or higher. For casual listening on the move, 128, 192 kbps is adequate. If you want flexibility without huge storage demands, aim for services offering 256 kbps or above.