These four formats cover almost every audio file you'll ever touch, and the differences between them come down to three things: how good it sounds, how big the file is, and where it will play. Once you understand that trade-off, choosing the right one is easy. Here's the plain-English version.
Uncompressed audio stores every sample exactly as it was recorded. It sounds perfect but the files are huge. To make files smaller, formats compress the data — and there are two kinds of compression:
With that in mind, here's where each format sits.
| Format | Type | Quality | File size | Best for |
|---|---|---|---|---|
| WAV | Uncompressed | Perfect | Very large | Editing, archiving, mastering |
| FLAC | Lossless | Perfect | Large (~half of WAV) | Storing a music library at full quality |
| MP3 | Lossy | Very good | Small | Sharing, streaming, universal playback |
| M4A (AAC) | Lossy | Very good (slightly better than MP3 at the same size) | Small | Apple devices, modern playback |
WAV stores audio uncompressed, so it's an exact copy of the sound with nothing lost. That makes it ideal while you're editing — every cut, fade and export keeps full quality — and for long-term archiving of a master recording. The downside is size: a few minutes of stereo WAV can run tens of megabytes. It's overkill for sharing or everyday listening, but it's the format you want as your working copy.
FLAC is lossless too, so it also sounds identical to the original — but it compresses smartly, typically landing around half the size of the equivalent WAV. That makes it the go-to for people who want to store a whole music collection at genuine full quality without WAV's bulk. The catch is compatibility: FLAC plays fine on computers and many modern apps, but not on every device or older player.
MP3 is lossy, so it discards some data to get dramatically smaller files — but at a decent bitrate (192 kbps or higher) most listeners can't tell the difference from the original. Its real superpower is compatibility: MP3 plays on essentially everything ever made, which is why it's still the default for sharing, podcasts, ringtones and general listening decades after it appeared. If you're not sure what to export, MP3 is the safe answer.
M4A files usually contain AAC audio, the format Apple adopted for iTunes and the App Store. AAC is also lossy, but slightly more efficient than MP3 — at the same file size it generally sounds a touch better. It's excellent across Apple devices and modern players. The only reason it isn't the universal default is history: MP3 got there first and is supported even more widely.
Technically yes — WAV is uncompressed and loses nothing, while MP3 discards some data. In practice, at 192–320 kbps most people can't hear the difference on normal equipment. WAV matters most while editing; for listening and sharing, MP3 is usually indistinguishable.
No. Once data has been removed by MP3 compression, converting to WAV can't bring it back — you just get a bigger file of the same quality. Quality is only preserved going from a lossless source, not recovered after the fact.
FLAC preserves full quality where MP3 doesn't, but the files are several times larger and less universally supported. "Better" depends on whether you value perfect fidelity (FLAC) or small, universal files (MP3).
Yes. You can open any of them and export to MP3 or WAV directly in the AudioTrim editor — for example, load a WAV you've been editing and download it as an MP3 when you're finished.
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