Audio File Formats Explained: MP3, WAV, FLAC, OGG, M4A Guide

Understanding audio file formats is essential whether you're splitting audio files, editing music, archiving recordings, or preparing audio for specific platforms. This comprehensive guide explains the most common audio formats, their strengths and weaknesses, and how format choice affects audio splitting quality.

Understanding Audio Compression

Audio formats fall into three main categories based on how they store audio data:

Uncompressed Audio

These formats store audio exactly as recorded with no data removed or compressed. They provide the highest quality but create very large files. Examples include WAV and AIFF.

Lossless Compression

Lossless formats compress audio to reduce file size but preserve all original audio data. When decompressed, the audio is bit-for-bit identical to the original. Examples include FLAC and ALAC (Apple Lossless).

Lossy Compression

Lossy formats achieve dramatic file size reductions by permanently removing audio data. They use psychoacoustic models to discard sounds humans theoretically can't hear. Examples include MP3, AAC, and OGG Vorbis.

File Size vs Quality Spectrum

Smaller Files
Lower Quality
Larger Files
Higher Quality

Low MP3 → High MP3 → OGG → AAC → FLAC → WAV

Common Audio Formats Explained

MP3 .mp3

Type: Lossy Size: ~1MB/min at 128kbps Quality: Good to Very Good

MP3 (MPEG Audio Layer III) is the most universally supported audio format. Developed in the late 1980s, it revolutionized digital audio by making music files small enough to share over early internet connections.

Best for: Music sharing, podcasts, audio for web, universal compatibility

  • Universal compatibility across all devices and platforms
  • Excellent compression with acceptable quality at 192-320kbps
  • Frame-based structure allows for clean splitting
  • Lossy compression means some quality loss
  • Re-encoding multiple times degrades quality

WAV .wav

Type: Uncompressed Size: ~10MB/min Quality: Perfect/Original

WAV (Waveform Audio File Format) is an uncompressed audio format that stores audio exactly as recorded. It's the standard format for professional audio production and editing.

Best for: Audio editing, professional production, archiving masters

  • Perfect quality—no data loss whatsoever
  • Industry standard for professional audio
  • Can be split anywhere without quality concerns
  • Very large file sizes (10x larger than MP3)
  • No metadata support (artist, album info)

FLAC .flac

Type: Lossless Size: ~5-6MB/min Quality: Perfect/Original

FLAC (Free Lossless Audio Codec) compresses audio without losing any data. It typically achieves 50-60% compression while maintaining bit-perfect quality when decoded.

Best for: Music archiving, audiophile listening, preserving recordings

  • Perfect quality with significant compression
  • Open-source and royalty-free
  • Excellent metadata support
  • Supports high-resolution audio (24-bit, 192kHz)
  • Not universally supported (no iTunes/older devices)
  • Larger than lossy formats

AAC / M4A .m4a, .aac

Type: Lossy Size: ~1MB/min at 128kbps Quality: Very Good (better than MP3)

AAC (Advanced Audio Coding) is the successor to MP3, offering better quality at the same bitrate. M4A is the container format commonly used for AAC audio, especially on Apple devices.

Best for: Apple ecosystem, iTunes, high-quality lossy audio

  • Better quality than MP3 at same file size
  • Default format for Apple Music and iTunes
  • Good compatibility with modern devices
  • Slightly less universal than MP3
  • Patent-encumbered (though widely licensed)

OGG Vorbis .ogg

Type: Lossy Size: ~1MB/min at 128kbps Quality: Very Good

OGG Vorbis is an open-source lossy codec that offers quality comparable to AAC. It's particularly popular in gaming, open-source software, and streaming applications.

Best for: Game audio, streaming, open-source projects, Spotify

  • Royalty-free and open-source
  • Better quality than MP3 at low bitrates
  • Used by Spotify for streaming
  • Limited hardware support (no iPods, some car stereos)
  • Less common than MP3 or AAC

AIFF .aiff, .aif

Type: Uncompressed Size: ~10MB/min Quality: Perfect/Original

AIFF (Audio Interchange File Format) is Apple's equivalent to WAV. It's uncompressed and provides identical quality to WAV, just with different metadata handling.

Best for: Mac-based audio production, Logic Pro, GarageBand

  • Perfect quality, no compression
  • Better metadata support than WAV
  • Standard in Mac audio workflows
  • Very large file sizes
  • Less common on Windows

Format Comparison Table

Format Type Quality File Size Compatibility Best Use
MP3 Lossy Good-Very Good Small Universal Sharing, Podcasts
WAV Uncompressed Perfect Very Large Universal Editing, Production
FLAC Lossless Perfect Medium Good Archiving, Hi-Fi
AAC/M4A Lossy Very Good Small Very Good Apple, Streaming
OGG Lossy Very Good Small Moderate Gaming, Open Source
AIFF Uncompressed Perfect Very Large Good (Mac) Mac Production

Choosing the Right Format

The best format depends on your specific use case. Here's a quick guide:

Podcasts

MP3 128kbps

Universal compatibility, small files for easy downloads

Music Streaming

AAC 256kbps

Great quality, efficient streaming

Music Archiving

FLAC

Perfect quality, reasonable size

Audio Editing

WAV

No quality loss during editing

Game Development

OGG Vorbis

Royalty-free, good compression

YouTube/Video

AAC 320kbps

High quality for video encoding

How Audio Format Affects Splitting

When splitting audio files, the format affects both quality and the splitting process:

Lossless Formats (WAV, FLAC, AIFF)

These formats can be split at any point without quality loss. The split files will have identical quality to the original. This makes them ideal when you need to edit or further process the segments.

Lossy Formats (MP3, AAC, OGG)

Lossy formats use frame-based encoding. For best quality, splits should occur at frame boundaries. ChunkAudio handles this automatically, ensuring clean cuts without re-encoding.

Frame-Boundary Splitting: MP3 files are divided into frames (about 26ms each at 44.1kHz). Splitting at frame boundaries preserves quality. Splitting mid-frame would require re-encoding, which adds another generation of quality loss.

Best Practices for Splitting

  • Keep original format when possible—convert only when necessary
  • Split before converting—if you need MP3 files, split the WAV first, then convert each segment
  • Avoid re-encoding—each conversion of lossy audio loses more quality
  • Use lossless for masters—always keep original quality versions
Pro Tip: ChunkAudio splits audio without re-encoding the data, preserving the original quality. When you split an MP3, the segments remain MP3s with identical audio quality to the source.

Bitrate Explained

Bitrate measures how much audio data is used per second, expressed in kilobits per second (kbps). Higher bitrates mean more data and generally better quality:

Bitrate Quality Level File Size (3 min song) Recommended Use
64 kbps Poor (AM radio) ~1.4 MB Voice only, low bandwidth
128 kbps Acceptable (FM radio) ~2.8 MB Podcasts, casual listening
192 kbps Good ~4.2 MB Music streaming, general use
256 kbps Very Good ~5.6 MB iTunes downloads, high quality
320 kbps Excellent (MP3 max) ~7 MB Audiophile MP3, professional

Sample Rate and Bit Depth

Beyond bitrate, lossless formats also specify sample rate and bit depth:

Sample Rate

How many times per second the audio is measured. Standard CD quality is 44.1kHz (44,100 samples per second). Higher rates like 48kHz (video standard) or 96kHz (high-resolution) capture more detail.

Bit Depth

How much data is captured per sample. CD quality is 16-bit, providing 65,536 possible values. Professional audio often uses 24-bit (16.7 million values) for greater dynamic range.

CD Quality: 44.1kHz sample rate, 16-bit depth, stereo = ~1.4 Mbps uncompressed (about 10 MB per minute of audio).

Split Any Audio Format

ChunkAudio supports MP3, WAV, FLAC, OGG, M4A, AIFF, and more. Split files while preserving original quality—all processing happens in your browser.

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Frequently Asked Questions

What is the difference between MP3 and WAV?

WAV is an uncompressed lossless format that preserves all audio data, resulting in large file sizes (about 10MB per minute). MP3 is a lossy compressed format that removes some audio data humans typically can't hear, reducing file sizes to about 1MB per minute at 128kbps. WAV is better for editing and archiving; MP3 is better for sharing and streaming.

Is FLAC better quality than MP3?

Yes, FLAC is lossless, meaning it preserves 100% of the original audio quality, while MP3 discards some audio information to achieve smaller file sizes. FLAC files are typically 3-4x larger than MP3 but maintain perfect audio fidelity. For casual listening, high-quality MP3 (256-320kbps) is usually indistinguishable from FLAC to most listeners.

What audio format should I use for splitting?

Use the same format as your source file when possible to avoid quality loss. For lossless splitting of WAV or FLAC files, keep the original format. For MP3 files, splitting at frame boundaries preserves quality. If you need to convert, choose based on your end use: MP3 for sharing, WAV for editing, FLAC for archiving.

What is OGG Vorbis used for?

OGG Vorbis is an open-source lossy audio format that offers better quality than MP3 at the same bitrate. It's commonly used in video games, web applications, and streaming because it's royalty-free. Spotify uses OGG Vorbis for streaming. It's a good choice when you need small files with good quality and don't need Apple device compatibility.

What's the best format for podcasts?

MP3 is the standard format for podcasts due to universal compatibility and good compression for speech audio. Use 64-96kbps mono for speech-only podcasts, or 128kbps stereo if music is included. MP3's smaller file sizes reduce hosting costs and ensure listeners can download episodes quickly.

Can I convert between formats without losing quality?

Converting from lossless to lossless (WAV to FLAC) preserves quality. Converting from lossless to lossy (WAV to MP3) loses some quality, but this is unavoidable with lossy compression. Converting between lossy formats (MP3 to AAC) loses additional quality and should be avoided—always convert from the original lossless source if possible.

T

Tim

Founder, ChunkAudio

Tim has worked with digital audio for over a decade, building tools that make audio processing accessible to everyone without sacrificing quality or privacy.