Move the sliderChoose your audio file and move the Volume slider. 100% is the original volume. You can change it while the audio is playing.
NormalizePress Normalize to raise the volume as much as possible without distorting the sound. It sets the loudest point of the track just below the maximum.
Watch the yellowThe waveform shows the result. Parts in yellow go over the maximum level and will sound distorted, so lower the volume until they disappear.
DownloadDownload the file as MP3 or WAV.
Levels are shown in dB, where 0 dB is the maximum a digital file can hold. A track whose loudest point is at -6 dB has room to be made twice as loud. Normalizing raises the whole track by the same amount, so it does not change how loud one part is compared to another.