Loona Volume Booster - Make Audio Louder Online Free
A voice note recorded too far from the microphone, a lecture you can barely hear, a video whose sound is whisper-quiet - this tool turns the volume up. Drag the slider, check the preview, mind the clipping warning, and download the louder audio as WAV.
How to make an audio file louder
- Click the box above or drag your audio file into it - MP3, WAV, M4A and OGG all work. The tool shows the file's current peak level.
- Drag the volume slider up - 200% is twice as loud in sample level, 300% is the maximum boost.
- If the red clipping warning appears, either lower the slider or tick "Normalize instead" to raise the volume safely to the maximum without distortion.
- Preview with "Play Boosted Preview", then click "Download Boosted WAV".
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Frequently Asked Questions
Is the Volume Booster free?
Yes. It is completely free with no sign-up, no watermark and no limit imposed by us.
Are my audio files uploaded to a server?
No. Your file is decoded and amplified 100% inside your browser with the Web Audio API. It never leaves your device.
What is clipping, and why the warning?
Digital audio has a maximum level of 100%. If boosting pushes samples past that limit, they are cut off flat - that is clipping, and it sounds like harsh distortion. The warning appears whenever your chosen boost would push the loudest peak past 100%, so you can lower the boost or use Normalize before it happens.
What does Normalize do?
Normalize measures the loudest moment in the whole file and scales everything so that peak lands exactly at 100% - the loudest the file can be without any clipping. Quiet recordings with one loud moment will not gain much; evenly quiet recordings gain a lot.
How many decibels is 300%?
300% volume is about +9.5 dB. 200% is about +6 dB and 50% is about -6 dB. The tool shows the exact dB value next to the slider as you drag.
How it works
Your file is opened right inside your browser and decoded into raw sound samples with the Web Audio API - nothing is uploaded to any server. The tool measures the highest sample in the file (its peak), multiplies every sample by your chosen gain in an offline render, warns you if the result would pass the 100% digital ceiling, and saves the result as a WAV file.
Worked example
You recorded an interview on your phone and the loudest moment only reaches 30% of the maximum level. You load the file, and instead of guessing a slider value you tick "Normalize instead". The whole interview is scaled up by about 3.3 times so its peak reaches exactly 100% - every word is now as loud as it can safely be, with no distortion, and you download the WAV.
Boosting and normalizing both raise noise along with the voice, so start from the cleanest recording you have.
More questions
Will boosting remove background noise?
No - boosting makes everything louder together, including any hiss or room noise in the original recording. It cannot clean audio, only raise its level.
Why is the downloaded file bigger than my MP3?
The export is WAV, the uncompressed format your browser can create natively. It keeps the audio exactly as rendered, but the files are larger than MP3. Any standard converter can turn the WAV into MP3 afterwards.
My recording is loud in one place and quiet elsewhere. What should I do?
That is a dynamics problem, not a plain volume problem. Normalize will only help a little, because the one loud moment sets the limit. Cutting out or separately boosting the quiet part with the Audio Cutter usually works better.
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Audio Cutter
Trim the start and end of any song, ringtone, lecture or voice note with a visual waveform - then download the cut as WAV.
Audio Joiner
Combine two or more audio files into one single track, in exactly the order you choose.
Voice Recorder
Record your voice with your microphone, listen back, and download the recording - nothing is ever uploaded.
Audio Speed Changer
Speed audio up or slow it down from 0.25x to 3x - great for lectures, podcasts and practice tracks.