Overview
WAV, also written WAVE, is a standard audio file container most often used to store uncompressed pulse-code modulation (PCM) audio. It was defined by Microsoft in collaboration with IBM as a practical way to store raw audio bitstreams on personal computers. The format is closely related to the RIFF (Resource Interchange File Format) family of containers, and its files normally use the .wav extension.
Structure and characteristics
At its core a WAV file uses a chunk-based structure derived from RIFF. The basic layout includes a header identifying the file as a RIFF/WAVE container and a sequence of chunks that describe codec parameters and hold the actual audio data. The most common encoding inside a WAV is linear PCM (LPCM), which stores uncompressed samples. Typical characteristics include sample rate (for example 44.1 or 48 kHz), bit depth (commonly 16- or 24-bit), and channel count (mono, stereo, multichannel).
- Common chunks: RIFF header, fmt (format) chunk, data (sample) chunk.
- Optional chunks: cue, LIST, fact (used by compressed streams), and metadata blocks.
- Encodings: LPCM by default; WAV can also contain other codecs.
Variants and extensions
Although WAV is most associated with uncompressed audio, the container can hold compressed audio streams as well. Specialized variations exist for professional workflows: the Broadcast Wave Format (BWF) adds metadata useful in radio and film production, and RF64 extends the format to overcome the 4 GB size limit imposed by 32-bit chunk sizes. These variants preserve compatibility with tools that understand the core RIFF/WAVE structure while adding fields for specific needs.
History and development
The WAV/WAVE convention grew out of efforts to standardize audio storage on desktop systems and is a sibling of other chunk-based formats such as IFF and AIFF used on platforms like the Amiga and Macintosh. Its association with Microsoft and PC ecosystems made it the default raw audio container on Windows platforms. The container model allowed developers to include new chunks or encodings without breaking basic playback compatibility.
Uses and compatibility
WAV files are widely used in audio recording, editing, sound design, and archival tasks because LPCM data is simple to process and preserves audio quality. Most audio editors, digital audio workstations, and media players support WAV. Because uncompressed WAV files are large compared with compressed formats, they are commonly used in production stages where fidelity matters and later converted to compressed formats for distribution. The container may also encapsulate compressed streams such as MP3, though this is less common.
Notable distinctions
WAV is often compared with AIFF: both store raw audio and metadata but come from different platform traditions. For archival and broadcast work, BWF and RF64 are important extensions that address metadata and file-size needs. When selecting a format, consider trade-offs between fidelity, file size, metadata requirements, and long-term compatibility; WAV remains a go-to choice for lossless, easily editable audio master files.
For more technical reference and implementation details, consult format specifications and developer guides from major platform vendors and standard bodies.