What Is Lossless Audio Compression?

Learn the pros and cons of using lossless formats

A stack of audio casette tapes

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You might think the word "lossless" is used for audio formats that don't use any compression. However, even lossless audio formats use compression to keep file sizes down to a reasonable level.

Lossless formats use compression algorithms that preserve audio data so the audio is exactly the same as the original source. This contrasts with lossy audio formats such as AAC, MP3, and WMA, which compress audio using algorithms that discard data.

Audio files are made up of sounds and silences. Lossless formats are able to compress the silences to almost zero space while maintaining all the sound data. 

Which Lossless Formats Are Used for Digital Music?

Examples of popular lossless formats used for storing music include:

Lossless Formats and Music Quality

If you download a music track in a lossless format from an HD music service, expect high-quality sound. On the other hand, if you convert low-quality music cassettes by digitizing them using a lossless audio format, the quality of the audio won't improve. 

Can You Convert From Lossy to Lossless?

It's never a good idea to convert from lossy to lossless. A song that has already been compressed using a lossy format will always be that way. If you convert it to a lossless format, you achieve only wasted storage space on your hard drive or mobile device. You can't improve the quality of a lossy song using this method.

Advantages of Using a Lossless Audio Format

Using a lossy format such as MP3 is still the most common method by which people store their music collections. However, there are clear advantages to building a lossless music library.

Perfect Music CD Backups

Ripping to lossless audio files gives you an exact bit-for-bit copy of the original music CD. This means that whatever audio formats come out in the future, you'll always have a perfect copy of the original.

Recover From Loss or Damage

Having your music in a lossless format lets you restore a damaged or lost original CD onto a blank CD.

Convert to Any Format

When music is in a lossless format, convert it to any format and achieve the highest quality that format can support. 

Disadvantages of Storing Your Music in a Lossless Format

Not as Compatible

Compared to formats like MP3, lossless formats aren't as well supported on hardware devices such as smartphones and tablets.

More Storage Space Needed

Lossless audio files typically require more storage space than lossily encoded ones.

Final Thoughts

Be aware of trade-offs and compatibility issues when selecting a file format for your audio files. Weigh the advantages and disadvantages of using a lossless format and make the best choice for your situation.