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LUFS Loudness Meter
Measure integrated loudness (LUFS), loudness range and true peak of a local audio file, and compare it with streaming and podcast targets.
Local workspace
Process a local file
Result
Your selected media stays on this device. AudioFetcher loads its processing engine, reads the file in browser memory, and creates the result locally.
Refresh or close the tab and the selected file and generated result leave browser memory.
Measures the whole file with the EBU R128 / ITU-R BS.1770 method. Platform targets are guides; each service applies its own rules. Files up to 160 MB; very long WAV files can exceed a phone's memory.
How to use LUFS Loudness Meter
- 1
Choose a local audio file up to 160 MB: a song, a master or a podcast episode in MP3, M4A, WAV, FLAC or another common format.
- 2
Select Measure loudness. The whole file is measured on your device with the EBU R128 method; long files take a little longer.
- 3
Read the integrated loudness in LUFS, the loudness range and the true peak in dBTP.
- 4
Compare the result with the targets table to see how streaming services and podcast apps will treat the file, then adjust your master if needed.
What this tool changes
Measure integrated loudness (LUFS), loudness range and true peak of a local audio file, and compare it with streaming and podcast targets.
Measures the whole file with the EBU R128 / ITU-R BS.1770 method. Platform targets are guides; each service applies its own rules. Files up to 160 MB; very long WAV files can exceed a phone's memory.
What LUFS measures
LUFS (Loudness Units relative to Full Scale) measures how loud audio sounds to people, not just how high its peaks go. It applies a K-weighting filter that roughly follows human hearing, then averages the signal over time. Integrated loudness is that average across the whole file, with very quiet passages gated out so silence and pauses do not drag the number down. A track at -9 LUFS sounds much louder than one at -16 LUFS even if both peak near 0 dBFS.
The meter follows ITU-R BS.1770 and EBU R128, the standards used by broadcasters and streaming platforms, via FFmpeg's ebur128 measurement running in your browser. A 1 kHz test tone at -23 dBFS on both channels reads -23.0 LUFS, as the standard specifies.
Integrated loudness, loudness range and true peak
- Integrated loudness (LUFS): the overall loudness of the file. This is the number platforms normalise to.
- Loudness range (LRA, in LU): how much the loudness varies between the quieter and louder parts. Heavily compressed pop may sit around 3 to 6 LU; film, classical and spoken conversation often go well beyond 10 LU.
- True peak (dBTP): the highest level of the waveform, including peaks that fall between samples and would appear after conversion. Keep it at or below -1 dBTP so MP3 or AAC encoding does not clip.
Streaming and podcast loudness targets
Spotify and YouTube turn tracks that are louder than about -14 LUFS down to that level, so pushing a master to -8 LUFS mainly costs dynamics rather than gaining loudness. Apple Music's Sound Check plays music at about -16 LUFS. Podcast guidelines commonly recommend about -16 LUFS for stereo and -19 LUFS for mono episodes. European broadcast follows EBU R128 at -23 LUFS.
The table under your result shows how far the file is from each target. Being louder than a target means that platform will turn it down; being quieter usually means it plays as is, which can make it sound weaker next to other tracks.
How to fix a file that is too loud or too quiet
To make a whole file quieter or louder by a fixed amount, change its gain and measure again. A file that is too quiet and already peaks near 0 dBTP cannot simply be turned up without clipping; it needs compression or limiting in an audio editor. For quick level matching of spoken recordings, the local Normalize Audio tool evens out the level, and Change Audio Volume applies a fixed gain.
Privacy and limits
The file is read and measured in your browser; it is not uploaded. Files up to 160 MB are accepted, which covers most podcast episodes as MP3. Very long WAV files can exceed a phone's memory, so measure an MP3 or FLAC version there. The meter reports measurements; it does not change your file.
LUFS Loudness Meter questions
Does LUFS Loudness Meter upload my file?
Your selected media stays on this device. AudioFetcher loads its processing engine, reads the file in browser memory, and creates the result locally.
What should I know before using LUFS Loudness Meter?
Measures the whole file with the EBU R128 / ITU-R BS.1770 method. Platform targets are guides; each service applies its own rules. Files up to 160 MB; very long WAV files can exceed a phone's memory.
What LUFS should I master to?
For streaming, around -14 LUFS integrated with true peak at or below -1 dBTP avoids being turned down by Spotify and YouTube. Louder masters are allowed but are normalised down anyway.
What is the difference between LUFS and dB?
dBFS measures signal level against digital full scale, mostly about peaks. LUFS measures perceived loudness over time with a hearing-based filter, which is what platforms use.
Is this the same measurement Spotify uses?
It uses the ITU-R BS.1770 method that loudness normalisation is based on. Each platform applies its own target and rules, so treat the comparison as a close guide.
Is my audio uploaded?
No. The measurement runs on your device with a local copy of FFmpeg. Only anonymous usage counts are recorded.