Volume Booster (Make Audio Louder)

What this volume booster actually does

A voice memo recorded from across the room, a lecture that you have to strain to follow, a track that sits well below everything else in your playlist: these all have the same problem, which is that the signal in the file is small. A volume booster fixes that by multiplying every sample by one number. That number is set in decibels, so +6 dB means each sample is about twice as large as before, and -6 dB means roughly half.

Because the same multiplication is applied everywhere, nothing about the character of the recording changes. The quiet parts stay quiet relative to the loud parts, the voice keeps its tone, and the background hiss goes up by exactly as much as the speech does. That is worth knowing before you start. A boost makes the whole file bigger; it does not clean it up, and it does not make a distant recording sound close.

The Volume knob covers minus 20 to plus 20 dB and starts at +6; a double-click puts it back there. The three boost presets (+3, +6 and +10 dB) are quick starting points, and a fourth preset, Quieter -6 dB, goes the other way for a file that is too hot. After every change the preview refreshes in about a quarter of a second, so you can listen while you adjust instead of guessing and exporting.

Reading the decibel table

The table in the Numbers tab is computed from the formulas, not measured from a file. Decibels describe a ratio, which is why the same number always means the same change whether your file starts out near silent or already strong. In amplitude terms, +6 dB is a factor of about 2.0, +10 dB is about 3.16, and +20 dB is exactly 10.

The last two columns are where people usually get surprised. The column labelled Volume as a percent shows what +6 dB looks like if you think in the percent scale of a phone or a media player: roughly 200 percent. But the perceived loudness column says something different. Human hearing does not track amplitude in a straight line; a rise of about 10 dB is commonly described as twice as loud. So +6 dB is clearly audible but not a doubling, and +3 dB is a small step you notice mostly when you flip back and forth.

Use that to set expectations. If a recording needs to feel twice as strong, you are looking at roughly +10 dB, and for many files that is more headroom than they have. If it only needs to sit level with the rest of a playlist, +3 to +6 dB is often enough.

Choosing a boost: starting numbers for common jobs

There is no single right setting because the right amount depends on how much room the file has left before it reaches full scale. Still, a few starting points work well. A quiet clip filmed on a phone is fair game too: MP4, MOV and WebM videos open here, and the page takes their sound, boosts it and saves audio only, as MP3 or WAV.

For a phone recording of a conversation or a lecture, try +6 dB first and listen for the point where the speech is comfortable without the noise floor getting in the way. If you need +10 dB or more, the recording was probably very quiet, and the hiss will come up with it. For a ringtone or an alarm clip, +3 to +6 dB is usually plenty, since these are already short and punchy. For a music track that sounds weak next to others in your library, start at +3 dB and add a little at a time; commercial music is often close to its ceiling already, so large boosts have nothing to work with.

If a file is already too hot, for example a clip that jumps out of a playlist and makes you reach for the control, use Quieter -6 dB or turn the knob below zero. Turning something down cannot cause clipping, so no peak handling is needed; saving as MP3 still re-encodes the file. Work in small steps, compare with the original after each one, and stop as soon as the result sounds right rather than when the number looks impressive.

The limiter and why clipping matters

Every digital file has a ceiling called full scale. A sample cannot be larger than that ceiling, so if a boost pushes a peak past it, the top of the waveform is sliced flat. That flattening is clipping, and it sounds like crackle, harshness or a buzzy edge on drums and consonants. Once a clipped file has been saved, the damage cannot be undone.

The option called Prevent clipping (limiter) is on by default for this reason. With it on, peaks that would go over -1 dBFS are held back, so you can push the boost further than a plain multiplication would allow and still get a clean file. The trade-off is simple: the more you ask of the limiter, the more the loudest moments are reduced, and a lot of limiting can make drums feel flatter and a dynamic track feel squeezed.

A good habit is to boost until the sound is where you want it, then switch the limiter off for a second and listen. If the result sounds the same, the limiter was barely working and you can leave it on for safety. If it sounds distorted without the limiter, you have found the point where the file has run out of room, and keeping the limiter on is the right call. Beyond that point, extra dB cost quality, so it may be better to settle for a smaller boost.

Peak and loudness readouts

Under the waveform, the tool shows two numbers for the result. The first is the peak in dBFS: how close the largest sample comes to full scale, where 0 is the limit. A peak at -1 means you have used all the room the limiter allows (it holds peaks at -1 dBFS); a peak of -12 means there is still space to grow.

The second is the loudness in LUFS, a measurement designed to follow how strong a piece of audio feels over time rather than how large its single biggest sample is. Two files with the same peak can feel very different, because a steady, dense track packs more energy under the same ceiling than a sparse one. Watching LUFS go up as you raise the boost is a good way to see that the effect is real, even when the peak has stopped moving because the limiter is holding it.

If your goal is to hit a specific loudness target for streaming or podcasts, that is a different job from raising a file by a fixed amount, and the normalize page handles it by measuring first and picking the gain for you. This tool is for when you know how many decibels you want, or when you want to simply try values and listen.

Mistakes that spoil a boosted file

The most common one is boosting a file that is already loud and expecting more. If a track peaks near 0 dBFS, there is nothing left to gain, and all the limiter can do is crush it. Check the peak readout before you assume the knob is the problem.

The second is boosting twice. Running a file through this tool, saving it, and running it again stacks the boosts, and each pass through an MP3 encoder adds a little more loss. Pick the final number once and apply it to the original file.

A third is judging by ear at a different playback level. A file played at a higher system setting will always seem better. Do not change the system volume between listens. The Result and Original buttons switch at the same moment of the track, so any difference you hear comes from the boost alone.

Last, remember that a boost cannot repair a bad recording. Distortion, wind noise and a muffled voice all get bigger along with everything else.

Loud playback has a cost to your ears. Keep headphones at a level where you can still hold a conversation, and take breaks, especially after applying a large boost, because a file that was gentle yesterday may be much stronger today.

Formats, bitrates and file size

WaveTinker opens whatever your browser can decode, which covers MP3, WAV, M4A and AAC, OGG and Opus, and FLAC, with files up to 250 MB. This page does not download anything from streaming services or websites; it works on files you already have, so use it on audio you own or have the right to edit.

When you save, choose MP3 at 128, 192, 256 or 320 kbps, or WAV at 16-bit or 24-bit. The size estimate appears before you commit. For a spoken recording, 128 kbps is usually enough and keeps the file small enough to send in a message. For music you plan to keep, 256 or 320 kbps preserves more detail. WAV is the safest choice if you intend to edit the file further, since it adds no extra compression loss, though it is much larger.

The saved name has the tool name added to it, so your original stays untouched next to the boosted copy. Because the output is a new encode, a boosted MP3 will not be bit-identical to the source apart from the gain, which is normal for any lossy format.

Where your file goes

Nowhere. The page decodes the audio inside your browser and does all the arithmetic there, so there is no upload step and no server that ever holds a copy. Close the tab and the working data is gone; the last file you opened is kept in this browser's storage on this device so the next tool can offer to continue with it, and clearing site data removes it.

The Copy settings link button writes the current boost into the page address. Send that address to someone and they get the same setting, though they will still need to load their own file. After saving, the Continue with links pass the processed result to the next tool, such as normalize or the converter, without leaving the browser.