Audio loudness normalizer
Adjust a recording toward a target loudness in LUFS, control its peaks, and check the measured loudness after processing.
Accepted files: .wav,.mp3,.m4a,.aac,.flac,.ogg,.oga,.opus,.webm,audio/*. Choose one file. Up to 256 MiB in total.
One recording up to 256 MiB and 5 minutes; target -40 to -5 LUFS, ceiling -9 to 0 dB. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose and a JSON report with loudness and peaks before and after. Set a loudness target, then check the measured result. Peak limiting can prevent reaching the target. Up to 1,000,000 characters. Review the settings before running.
Your result
How to use Audio loudness normalizer
- Choose the recording.
- Enter the target loudness in LUFS and the peak ceiling.
- Choose true peak or sample peak mode.
- Normalize, check whether the target was reached and download the WAV.
Useful next steps
One recording up to 256 MiB and 5 minutes; target -40 to -5 LUFS, ceiling -9 to 0 dB. WAV is read with every sample intact; other formats are decoded by your browser at 48 kHz. Everything is processed on your device and nothing is uploaded. Download: WAV in the source format or the format you choose and a JSON report with loudness and peaks before and after.
Measurement
Integrated loudness is measured using K-weighting, 400 ms blocks, and absolute and relative gates from ITU-R BS.1770-4. The gain stage turns the whole file up or down by the difference to your target. This stage preserves relative dynamics; any subsequent peak limiting can change them.
When limiting is needed
If the gain would push the peaks above the ceiling, a look-ahead limiter holds them down. The report says whether the limiter was applied and whether the result is within 0.5 LU of the target. Common targets are -16 LUFS for podcasts and -14 LUFS for music streaming, but check the current guidance of the service you publish to.
Silent files
A recording that is silent or almost silent has no measurable loudness, so it cannot be normalized.