FLAC to MP3: How to Convert and What You Lose
Published on March 1, 2026
FLAC files are lossless, meaning they store every detail of the original recording. MP3 files are lossy, meaning they throw out audio data to shrink the file. Converting FLAC to MP3 typically reduces file size by 70-80%, but you permanently lose some audio information in the process.
What Gets Lost in the Conversion
MP3 encoding removes frequencies most people cannot hear, like sounds masked by louder tones and very high frequencies above 16-18kHz. At 320kbps, the difference is nearly impossible to detect without studio headphones and a trained ear. At 128kbps, you may notice artifacts on cymbals, acoustic guitars, and breathy vocals. The loss is permanent: you cannot get the original quality back from an MP3.
Which Bitrate Should You Choose
- 320kbps: Closest to the original. Use this if storage is not a concern and you want the best MP3 quality.
- 192kbps: Good balance. Most listeners cannot tell the difference from 320kbps in everyday listening.
- 128kbps: Smallest file size. Fine for spoken word, podcasts, or background music. Not ideal for critical listening.
For a detailed breakdown of what each bitrate means, read audio bitrate explained. And if you want to understand the broader MP3 quality tradeoff, see our MP3 vs WAV comparison.
FLAC vs MP3: File Size Comparison
A 4-minute song stored as FLAC (16-bit, 44.1kHz) is roughly 25-35MB. The same track at MP3 320kbps is about 9MB. At 128kbps, it drops to around 4MB. If you have a large FLAC library, converting to MP3 frees up significant storage space.
When to Keep FLAC
Keep your FLAC originals if you plan to re-encode later. Since FLAC is lossless, you can always create new MP3s from it. Converting MP3 to FLAC does nothing useful, since the lost data is already gone. Think of FLAC as your master copy and MP3 as the portable version.
How to Convert
The fastest way is a browser-based converter. Our WAV to MP3 converter handles audio conversion directly in your browser with no upload to any server. For large collections, you can also compress audio files to reduce file size while keeping the format you want. Wondering whether to keep FLAC or switch to WAV? See WAV vs FLAC.