Lossless

In-Depth Explanation

Lossless audio is a type of data compression that perfectly reconstructs the original uncompressed audio file without discarding any information. Unlike lossy formats (MP3, AAC, OGG) that permanently remove frequencies to shrink file size, lossless formats like FLAC and ALAC reduce file size by about 50% while remaining bit-for-bit identical to the original WAV when played back.

How Lossless Audio Works

When you export a song from a DAW, it is typically saved as an uncompressed WAV or AIFF file. These files are massive. A 16-bit/44.1kHz stereo WAV file takes up roughly 10 MB per minute of audio. To make files easier to stream or store, they must be compressed.

Compression falls into two categories:

• Lossy compression (MP3, AAC, OGG): These algorithms shrink file size dramatically (up to 90%) by analyzing the audio and permanently discarding frequencies that human ears struggle to perceive. Once converted to MP3, that data is gone forever.
• Lossless compression (FLAC, ALAC): These algorithms act like a ZIP file for audio. They analyze the data for redundancies and pack it more efficiently. When the file is unpacked for playback, it is identical to the original WAV.

Common Lossless Formats

FLAC (Free Lossless Audio Codec) is the industry standard for lossless audio. It is open-source, widely supported by almost all software and hardware players, and offers excellent compression ratios. Spotify's lossless tier, Tidal, Amazon Music HD, and Qobuz all stream FLAC files.

ALAC (Apple Lossless Audio Codec) is Apple's proprietary lossless format. It achieves similar file size reductions to FLAC but was designed for the Apple ecosystem. Apple Music streams ALAC files at resolutions ranging from 16-bit/44.1 kHz (CD quality) up to 24-bit/192 kHz.

WAV and AIFF are technically uncompressed, not lossless. They take raw digital audio data and wrap it in a container with no compression at all. They offer perfect quality but at the cost of maximum file size.

Real-World Example

As of 2026, every major streaming platform except YouTube Music offers a lossless tier. Apple Music included lossless at no extra cost since 2021. Amazon Music HD and Tidal followed. In summer 2025, Spotify finally launched its long-awaited lossless streaming option for Premium subscribers, streaming FLAC files up to 24-bit/44.1 kHz.

A 3-minute pop song at 16-bit/44.1 kHz takes up approximately 30 MB as a WAV file. Compressed to FLAC, that same file drops to about 15 MB with zero loss in audio quality. The same song as a 320 kbps MP3 takes up roughly 7 MB, but the MP3 has permanently discarded high-frequency content above approximately 16 kHz and smeared transient detail.

For a producer uploading to a digital distributor, the delivery format matters. If you upload an MP3 to Spotify, they will compress it again for their lower-bitrate tiers, causing generation loss (double compression). Uploading a 24-bit WAV gives the platform the highest quality source file so it can handle all codec conversions from a clean master.

Why It Matters for Independent Artists

1. Always archive in lossless. Never store your final masters as MP3s. Bounce your final mixes and masters as uncompressed WAV files and archive them as WAV or FLAC. If you ever need to remaster or re-release, you need the full-resolution source.
2. Upload lossless to distributors. Always upload 16-bit or 24-bit WAV files to your distributor. Spotify, Apple Music, and YouTube need the highest quality source file so they can handle the lossy compression for their standard streaming tiers themselves.
3. Do not double-compress. If you upload an MP3 to your distributor, the platform will compress it again for their lower-bitrate streams. This double compression causes audible degradation, particularly in the high frequencies and transient detail.

Read our guide on mastering for streaming platforms to understand how lossless delivery affects your mastering chain, and our comparison of music distribution services to see which distributors accept high-resolution uploads.

Related Terms

• Bit Depth
• Sample Rate
• DAW (Digital Audio Workstation)
• Mastering
• Compression
• Lossy - The counterpart to lossless: compression that permanently discards audio data