About the Audio Normalizer
Normalize audio to a standard loudness, measured in LUFS, the unit Spotify, YouTube, Apple and broadcasters use. Bring a quiet podcast up to −16 LUFS, a song to −14 LUFS for streaming, or a video's sound to −23 LUFS for broadcast, so it plays at the same perceived volume as everything around it.
The tool measures your file, changes its level by exactly the amount needed, and measures the result again so you can see where it landed. It runs in your browser, up to 100 MB.
How it works
Loudness in LUFS follows the EBU R128 and ITU-R BS.1770 standards: the sound is weighted the way the ear hears it, quiet gaps are left out, and the average is taken over the whole file. That makes it a far better guide to how loud something sounds than its highest peak.
The level of the whole file is then changed by one fixed amount: the target minus the measured loudness. A file at −20 LUFS normalised to −14 LUFS gets +6 dB. Because every sample is multiplied by the same number, the dynamics, the difference between loud and soft parts, stay exactly as they were.
If reaching the target would push the loudest peaks above −1 dB, the limiter holds just those peaks below it. The result shows the measured loudness, the change made and the loudness afterwards.
Assumptions and limits
- Targets from −36 to −5 LUFS; the presets cover streaming, Apple, EBU and US broadcast.
- Peaks are held at −1 dB of sample level; true-peak meters may read a few tenths higher.
- A file that is almost silent (below −70 LUFS) can't be normalised.
Worked examples
A quiet podcast
A voice recording measuring −24 LUFS needs +8 dB to reach the −16 LUFS that Apple Podcasts recommends.
A song for streaming
A master at −9 LUFS is turned down 5 dB to −14 LUFS, the level Spotify and YouTube play at anyway.
Broadcast delivery
A clip at −18 LUFS is lowered by 5 dB to meet the EBU R128 broadcast target of −23 LUFS.
How to use the Audio Normalizer
- Pick the audio. Song, podcast, voice-over or video sound.
- Choose the loudness target. −14 for streaming, −16 for podcasts, and more.
- Download at that level. With the before and after loudness shown.
Frequently asked questions
What does normalizing audio do?
It changes the volume of a whole file so it sounds as loud as a chosen standard. Here the loudness is measured in LUFS and the whole file is raised or lowered by one amount, so nothing else about the sound changes.
Which LUFS target should I use?
Use −14 LUFS for Spotify, YouTube and most streaming, −16 LUFS for Apple Music and podcasts, −23 LUFS for European broadcast and −24 LUFS for US television. If unsure, −14 LUFS is a good general choice for music and video.
What is the difference between LUFS and peak normalization?
Peak normalization makes the single loudest sample hit a level, which says little about how loud the file sounds. LUFS measures the average loudness as people hear it, so two files normalised to the same LUFS sound equally loud.
Will normalizing make my audio distort?
Raising a file can push its peaks past the maximum level. With Prevent distortion on, those peaks are held just below −1 dB while the rest gets the full change. The result tells you when this happened.
Does normalization compress the dynamics?
No. The whole file is changed by one fixed gain, so quiet and loud parts keep the same difference. Only peaks that would go above −1 dB are touched, and only when the limiter is needed.
This tool runs entirely in your browser. What you enter or upload stays on your device and is never sent to our servers.