Understanding Peak and RMS Volume Normalization
What this tool does
Recorded audio rarely arrives at a consistent volume. One clip peaks near the ceiling while the next sits ten decibels lower, and listeners are left reaching for the volume control. This tool measures your file and then rewrites its gain so the level lands where you want it.
When you drop in a track, it decodes the audio and reports two numbers in decibels: the peak level (the single loudest sample) and the RMS level (the average energy the ear perceives as loudness), alongside the duration and channel count. Those measurements are what each adjustment mode acts on.
Three ways to adjust the level
Maximize Volume applies peak normalization: it raises the whole signal until the loudest sample reaches the ceiling, which is the safest way to make a quiet recording as loud as possible without clipping. Balance Volume works on the RMS level instead, pushing perceived loudness toward a consistent target so several files play back at a similar volume rather than matching only their peaks.
Custom Adjustment skips the measurement targets and shifts gain by an exact number of decibels — useful when you already know a file needs, say, +3 dB or a small cut to sit better in a mix.
Example: leveling three interview clips
Say you have three interview recordings: one loud, one faint, and one in between. Played back to back they are jarring. Choose Balance Volume, aim for a common average target, and each clip is nudged toward the same perceived loudness — the quiet one comes up, the loud one eases back. Enable Prevent Distortion first, and any peak that would otherwise overshoot the ceiling is caught by the limiter instead of crackling.
Notes and edge cases
Boosting gain also lifts the noise floor, so a hissy recording sounds hissier once maximized — normalization changes level, not the signal-to-noise ratio. The limiter prevents clipping but can slightly flatten sharp transients when pushed hard, so use the before/after preview before you download.
Input accepts MP3, WAV, OGG, FLAC, AAC, and M4A up to 500MB; output is MP3 or WAV, with WAV staying lossless for further editing. The decode-and-encode pipeline runs locally through the Web Audio API, which means very long files depend on how much memory the browser can spare.