UtilibyWritten by the Utiliby editorial team · Last updated October 13, 2026 · Rules and formulas reviewed October 2026
What this free audio volume booster does
A volume booster makes a quiet recording louder. Maybe a lecture was recorded far from the microphone, an old MP3 is much quieter than the rest of your playlist, or a voice message is hard to hear. Turning the volume knob on your device only helps while you listen. This free online tool changes the audio file itself, so it is louder everywhere you play it. It works in your browser, so your file is not uploaded.
It offers three ways to raise the level: a simple gain in decibels, peak normalization to a target, and loudness normalization in LUFS, which is what streaming and broadcasting use. A built-in limiter holds the loudest peaks under a ceiling so that boosting does not cause clipping. Meters show the peak, loudness and number of clipped samples before and after, and two waveforms let you see the change.
How to make audio louder in four steps
- Load your file. Drop it on the box. The waveform and the current peak and loudness appear.
- Choose a mode. Use Boost by dB for a quick change, Normalize peak for a target peak, or Normalize loudness to hit a LUFS target.
- Compare. Press Play and switch between Result and Original. Check the clipped samples count in the summary. It should be zero.
- Download. Choose MP3 or WAV and click Download louder file.
Decibels explained
Decibels (dB) measure level on a logarithmic scale because hearing is logarithmic. A change of 1 dB is barely noticeable, 3 dB is clearly audible, and about 10 dB sounds twice as loud. In terms of amplitude, 6 dB is a factor of two, and 20 dB is a factor of ten.
| Gain | Amplitude factor | How it sounds |
|---|---|---|
| +3 dB | 1.41 | Slightly louder |
| +6 dB | 2.0 | Clearly louder |
| +10 dB | 3.2 | About twice as loud |
| +20 dB | 10 | Much louder |
| -6 dB | 0.5 | Clearly quieter |
Gain, peak normalization or loudness normalization?
- Boost by dB multiplies the whole file by a fixed amount. It is predictable. If the file already has loud peaks, they may clip unless the limiter is on.
- Normalize peak finds the highest peak and scales the file so that it reaches your target, such as minus 1 dB. It is safe because it never clips, but a single loud click can limit how much it can boost the rest.
- Normalize loudness measures the perceived loudness of the whole file and sets it to a target in LUFS. It is the best choice when you want files to sound equally loud, such as podcast episodes or a playlist. The limiter catches peaks that the boost would push over the ceiling.
LUFS targets and where they come from
Broadcasters and streaming services normalize programs to a loudness target so that viewers and listeners do not have to keep reaching for the volume control. The numbers below are common reference points. Services change their settings from time to time, so check the current guidance for the platform you publish on.
| Use | Typical target |
|---|---|
| European broadcast (EBU R 128) | -23 LUFS |
| Podcasts (stereo, AES recommendation) | -16 LUFS |
| Podcasts (mono) | -19 LUFS |
| Apple Music and Sound Check | about -16 LUFS |
| Spotify and YouTube | about -14 LUFS |
Platforms usually turn down music that is louder than their target, but they do not always turn up music that is quieter. A file that is too quiet can end up quieter than its neighbors, which is why a loudness target matters.
How the limiter protects your audio
If you add 12 dB to a recording that already peaks at minus 6 dB, the loudest parts would be 6 dB above the maximum and would clip. The limiter looks about five milliseconds ahead, finds those peaks, and lowers the gain just enough, with a smooth ramp, so they land at or below the ceiling. It then lets the gain recover slowly, over about 80 milliseconds. Because only the peaks are touched, the rest of the file stays loud.
A limiter is not magic. If you ask it to remove many decibels, the music will sound squashed and flat, with less punch. The summary tells you how much the limiter reduced the peaks. If the number is large, lower the boost or accept a quieter result.
Tips for the best result
- Fix quiet recordings at the source when you can. Moving the microphone closer helps more than any boost.
- Boost the lowest amount that gets you where you need to be. Noise rises along with the voice.
- For speech, aim for minus 16 LUFS with a ceiling of minus 1 dB.
- Keep the original file. Boosting and re-saving to MP3 is not reversible.
- Listen to the end of the file. A loud ending can trigger the limiter even if the start sounds fine.
- Use WAV when you plan to do more editing afterwards.
Common uses
- Quiet voice memos and lectures made from far away.
- Old MP3s and ripped CDs that play at a lower level than the rest of a playlist.
- Podcast episodes that need a consistent loudness.
- Video and interview audio that is hard to hear on a phone.
- Ringtones and alarms that need to cut through a noisy room.
Troubleshooting
- The result crackles: the file clipped. Turn the limiter on, lower the gain, or lower the loudness target.
- It is still too quiet: a peak target cannot go beyond the loudest peak. Use Normalize loudness, which works from the average level.
- The loudness reads n/a: the file is very short or almost silent, so it cannot be measured.
- There is a lot of hiss: boosting raised the noise. Use a smaller boost or a noise reduction tool first.
- MP3 export fails: the encoder could not be downloaded. Choose WAV or check your connection.
Privacy and how it works
Your browser decodes the file into samples. The page measures loudness with the ITU-R BS.1770 method, multiplies the samples by the gain, runs the limiter if needed, and encodes the result locally. Nothing is uploaded, stored or logged. The MP3 encoder library loads from a public CDN the first time you choose MP3, but your audio is not part of that request.
What this tool does not do
It changes the overall level and limits peaks. It does not remove noise, balance quiet and loud passages the way a compressor does, or repair clipped audio that was recorded too loud. The peak shown is the highest sample value, not a true-peak measurement, so leave a little headroom if you will convert the file again.
Frequently asked questions
How do I make a quiet audio file louder for free?
Load the file, choose Boost by dB, and set a gain such as 6 or 10 dB. Keep the limiter on so the loudest parts do not clip. Compare Result and Original, then download. Everything happens in your browser.
How many dB should I add?
Every 6 dB doubles the amplitude, and about 10 dB sounds roughly twice as loud. For a file that is a little quiet, 3 to 6 dB is enough. For a very quiet recording, use Normalize loudness or Normalize peak, which work out the right amount for you.
What is the difference between normalizing peak and loudness?
Normalize peak raises the file until its highest single peak reaches a target such as minus 1 dB. A file with one loud spike may still sound quiet. Normalize loudness measures how loud the file sounds on average, in LUFS, and sets that to a target, which better matches what you hear.
What is LUFS?
LUFS means loudness units relative to full scale. It is a measure of perceived loudness defined in the ITU-R BS.1770 standard, which weights frequencies the way ears hear them and ignores silence. It is the unit used by streaming services and broadcasters.
Which LUFS target should I use?
Minus 16 LUFS is a common target for podcasts, minus 14 LUFS is close to what many streaming services play, and minus 23 LUFS is the European broadcast standard. If you only want a louder file for yourself, minus 16 is a safe, comfortable level.
What does the limiter do?
A limiter keeps peaks under a ceiling by lowering the gain for a few milliseconds around each loud peak. It lets you raise the overall level without the harsh crackle of clipping. Heavy limiting makes music sound flatter, so use the smallest boost that does the job.
What is clipping and why avoid it?
Digital audio cannot go above its maximum level. If a boosted wave would exceed it, the top is cut flat, which sounds like crackle or harshness. The tool counts clipped samples in the result and warns you.
Will boosting also boost the noise?
Yes. Gain raises everything, including hiss and background noise. If the noise is already noticeable, boosting makes it more so. Record closer to the microphone next time, or use a noise reduction tool.
Does it change the quality?
WAV output has no further loss. MP3 output is compressed again, so use 192 kbps or higher. Heavy boosting of an already compressed file can reveal its artifacts.
Is my audio uploaded?
No. The file is decoded and changed on your device. The page downloads an open-source MP3 encoder from a public CDN the first time you choose MP3, but your audio is not sent anywhere.
Can I make a video louder?
You can load a video file and boost its audio track, but the download is an audio file. The tool does not return video.
Why is the peak ceiling minus 1 dB and not zero?
A little headroom avoids distortion when the file is converted to MP3 or played through different equipment. Minus 1 dB is a common safe value.
Can I turn the volume down too?
Yes. Use a negative gain, such as minus 6 dB. This is useful to match the level of another file.
Is the loudness reading exact?
It follows the ITU-R BS.1770 method with gating, so it is a good estimate. Certified meters add details such as true-peak detection and extra filtering, so treat the numbers as close, not official.
Will it work on my phone?
Yes, in a modern browser. Long files need more memory than short ones.
Is it safe for my speakers and ears?
Large boosts can be very loud. Turn your volume down before you press Play, increase it slowly, and avoid long listening at high levels.
What can I print or save from the page?
Print / save summary prints the settings, the peak and loudness before and after, and the waveforms. Copy summary copies the same values as text. The louder audio file is the main download.
Sources and further reading
- ITU-R Recommendation BS.1770-4, Algorithms to measure audio programme loudness and true-peak audio level.
- EBU R 128, Loudness normalisation and permitted maximum level of audio signals.
- AES TD1004.1.15-10, Recommendation for Loudness of Audio Streaming and Network File Playback.
- Spotify for Artists, Loudness normalization, and Apple Support, Sound Check, for streaming loudness behavior.
- LAME project and the lamejs encoder, the open-source MP3 encoder used for MP3 output.
Sources were consulted in October 2026. Standards and rules can change, so always check the official page for your situation.