See your audio as a waveform, right in the browser
A waveform viewer turns an audio file into the familiar shape that audio editors show: amplitude over time. It is handy for spotting silent gaps, fades, transients, and — importantly — clipping, all without installing software or uploading your file anywhere.
How it works
The file is decoded to raw PCM with AudioContext.decodeAudioData, then the channels are mixed to a single mono Float32Array. To draw, the Canvas width is divided across the samples so each pixel column covers a fixed bucket. For that bucket the tool computes the minimum and maximum sample value and draws a vertical line between them — this is a peak (min/max) waveform, the same approach used by DAWs.
Clipping is detected when any sample in a column reaches ±0.999 or beyond; those columns are drawn in red. The overall peak level is reported in dBFS using 20 · log10(peak), where the loudest possible sample is 0 dBFS.
Reading what you see
The vertical dimension represents amplitude — how loud the audio is at that moment. A waveform that fills the full height of the view has peaks near 0 dBFS. A waveform that sits at roughly half height has peaks around −6 dBFS. One that barely rises off the centre line is very quiet or potentially silent.
The horizontal dimension is time. Zooming in stretches time on screen, making individual transients (drum hits, consonants, click sounds) visible as sharp spikes. Zooming out gives a macro view useful for spotting where a long recording has a sudden loud section or a sustained silence.
What red clipping regions tell you
Red-highlighted columns contain samples at or above full scale — they have been digitally clipped. This can happen because:
- Gain was set too high during recording. The most common cause; the preamp or ADC saturated before the signal reached the DAW.
- A plugin added gain post-recording. Compressors, limiters or EQ with makeup gain can push a previously clean recording into clipping.
- A file was normalised to 0 dBFS without a true-peak ceiling. The inter-sample (true) peak may have been above full scale before normalisation, and normalising to 0 dBFS worsened it.
If you see red, the source recording needs to be re-captured or de-clipped before mastering. Reducing the level of a clipped export does not remove the distortion — it only makes the distorted audio quieter.
Practical uses
- Pre-mastering check: Confirm your mix export peaks are a few dB below 0 dBFS before sending to a mastering engineer. This viewer gives you a quick visual confirmation without opening a DAW.
- Podcast quality control: Load the finished episode and scan for any accidental clipped sections caused by a guest with a loud microphone, before publishing.
- Archiving old recordings: Digitised tapes or vinyl often carry unexpected distortion that is difficult to hear at low volume. The viewer surfaces it visually.
Tips and notes
- Use the zoom slider to expand the start of the file; it makes count-in clicks, pops, or DC offset easy to see.
- Red columns indicate clipping. If you see them, reduce gain on the source and re-export before mastering or publishing.
- A peak well below 0 dBFS (for example -6 dBFS) leaves headroom — useful before applying further processing.
- Because everything runs locally, large files consume browser memory; trim very long recordings if the page slows down.