How to use
- Add files; press Measure only to see their loudness, range and true peak.
- Choose a target (for example −16 LUFS for podcasts) and a true-peak ceiling (−1 dBTP).
- Normalize, check the re-measured result, and download the files or a CSV report.
Worked example
A track measuring −20.3 LUFS with a −4.1 dBTP peak needs +4.3 dB to reach −16 LUFS; the peak becomes about +0.2 dBTP, so the limiter brings it down to −1 dBTP.
Supported formats and limits
| Input | MP3, WAV, M4A, Ogg, FLAC, WebM |
|---|---|
| Output | WAV (24-bit), FLAC, MP3, M4A (AAC), Ogg Opus, CSV report |
| Limits | 50 files per batch; about 23 minutes of 48 kHz stereo per file (decoded into memory). |
| Engine | BS.1770-4 K-weighting with gating, 4× oversampled true-peak, gain + look-ahead limiter |
Limitations
- Raising loudness also raises background noise.
Questions
What happens when the gain pushes the peak too high?
With the true-peak limiter on, peaks are held under the ceiling. A track at -20.3 LUFS with a -4.1 dBTP peak needs +4.3 dB to reach -16 LUFS; that would put the peak near +0.2 dBTP, so the limiter brings it down to -1 dBTP.
Which target should I choose?
Use the level your platform or publisher asks for. The presets are -14, -16 and -23 LUFS, and a custom target is available. A -1 dBTP ceiling leaves room for MP3 or AAC encoding; -2 is safer at low bitrates.
Privacy
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