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utility
LUFS Loudness Normalizer
Measure loudness and normalize to platform standards. Free, private, runs in your browser.
How it works
01
Drop your audio file or click to upload. MP3, WAV, and most formats work.
02
The tool measures your audio's loudness in LUFS using K-weighted analysis.
03
Pick a target (Spotify, YouTube, Apple Podcasts, etc.) and normalize. Download the result.
No file uploadNo signupNo ads100% browser-based
Frequently asked questions
What is LUFS?
LUFS stands for Loudness Units relative to Full Scale. It measures perceived loudness, not just peak volume. Streaming platforms and broadcasters use LUFS to ensure consistent playback levels across content.
What LUFS should I target for Spotify?
Spotify normalizes to -14 LUFS. If your audio is louder, Spotify turns it down. If it's quieter, Spotify turns it up. Mastering to -14 LUFS gives you the most control over how your music sounds on the platform.
What LUFS should I target for podcasts?
Apple Podcasts recommends -16 LUFS. This is also a good general target for spoken content. It gives enough headroom while keeping the audio loud enough for comfortable listening.
Will normalizing cause clipping?
If boosting volume would push peaks above 0 dBFS, the tool applies a hard limiter to prevent clipping. A warning appears when limiting is needed.
How accurate is the LUFS measurement?
The tool uses K-weighted loudness measurement based on ITU-R BS.1770, the same standard used by streaming platforms and broadcasters. It applies a high-shelf pre-filter and high-pass filter before computing integrated loudness.
Does this upload my audio to a server?
No. The loudness measurement (ITU-R BS.1770 K-weighting) and the gain adjustment both run locally in your browser. Unlike some desktop loudness tools, nothing is sent to a remote server.
Will Spotify raise my track's volume if it's quieter than -14 LUFS?
Yes. Spotify applies gain to bring quiet tracks up to -14 LUFS. But if your track lacks headroom, this can push peaks above 0 dBFS and cause clipping. Normalize to -14 LUFS here before uploading so Spotify does not need to adjust it.
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