WAV Oscilloscope - Online Visualize Audio Waveform & Spectrum

A WAV oscilloscope visualizes audio waveforms by plotting amplitude over time. It reads the PCM samples from your WAV file and renders them on a canvas, allowing you to see the shape of the sound. The spectrum view uses FFT (Fast Fourier Transform) via the Web Audio API to display frequency content in real-time during playback, showing which frequencies are present at any moment.

Although the tool is called "WAV Oscilloscope," it supports all audio formats that your browser can decode — including MP3, OGG, FLAC, AAC, and more. The Web Audio API's decodeAudioData() handles decoding automatically. For WAV files specifically, we also parse the header to display original bit depth information.

Use the +/- buttons or mouse scroll wheel to zoom in/out horizontally. When zoomed in, click and drag on the waveform to pan left and right. The overview bar below the main waveform shows your current viewport — you can also drag the highlighted region there to navigate quickly. Press 0 or click the expand button to reset zoom. Keyboard shortcuts: Space to play/pause, +/- to zoom.

The spectrum analyzer uses the Web Audio API's AnalyserNode, which processes audio in real-time as it flows through the audio graph. This means the FFT spectrum is computed live during playback. When audio is paused, there's no signal flowing, so the spectrum is static. This design ensures accurate, real-time frequency visualization that reflects exactly what you're hearing.

The bright waveform shows audio amplitude — taller sections are louder. The horizontal center line represents silence (zero crossing). Grid lines mark time divisions (seconds) and amplitude levels. For stereo files, the upper half shows the left channel and the lower half shows the right channel. The orange cursor line indicates the current playback position. In the spectrum view, taller bars indicate stronger frequencies, with the gradient coloring from cyan (low energy) to warm yellow/white (high energy).

No. All processing happens entirely in your browser. The file is read locally using the FileReader API, decoded in memory via the Web Audio API, and rendered on HTML5 canvases. No data is ever sent to any server. Your audio files remain completely private and secure on your device.