Waveform Viewer

About Waveform Viewer

Why pay $30/month for Audacity Pro or Adobe Audition just to see a waveform? Podcasters spot dead-air gaps and umm/ahh clusters at a glance; musicians find the kick-drum hit to align a snare sample; voice actors check for breath pops and S-clicks; editors verify levels stay above the silence threshold and below clipping. This tool delivers serious analysis free in your browser: zoomable waveform (100x), a true windowed STFT spectrogram with a selectable window (Hann, Hamming, Blackman, Rectangular), selectable FFT size (512-4096) and a sample-rate-aware linear or log frequency axis, so a 1 kHz tone really lands at 1 kHz and you can hunt 50/60 Hz hum, hiss, sibilance and codec artifacts. Add stereo split view to debug L/R balance, dBFS peak meters with peak-hold readouts, A-B loop for re-listening tricky sections, draggable markers, and PNG/SVG export. Supports MP3, WAV, FLAC, OGG, AAC, M4A, OPUS up to 500MB. All processing browser-local — your unreleased tracks never touch a server.

What audio formats are supported?

All common audio formats are supported including MP3, WAV, OGG, AAC, M4A, FLAC, OPUS, and more. The waveform is generated from the decoded audio data.

What is a waveform?

A waveform is a visual representation of an audio signal showing amplitude (volume) over time. The height represents loudness - taller peaks mean louder sounds, shorter sections mean quieter sounds. It helps you see the structure of your audio at a glance.

What is a spectrogram?

A spectrogram displays frequencies over time using colors. Brighter colors indicate louder frequencies. It's useful for identifying specific sounds, analyzing speech patterns, and detecting noise or artifacts in audio.

How do I read frequencies in the spectrogram?

The spectrogram is a real windowed Short-Time Fourier Transform (STFT): time runs left to right, frequency runs bottom (0 Hz) to top. The top of the axis is the Nyquist frequency, which is exactly half the sample rate (fs/2) — so a 44.1 kHz file tops out near 22 kHz and a 48 kHz file near 24 kHz. Each FFT bin spans fs/N hertz, where N is the FFT size you pick: a larger FFT (e.g. 4096) gives finer frequency resolution to separate close tones, while a smaller FFT (512) gives sharper time resolution for transients. Choose a Hann or Hamming window to reduce spectral leakage when measuring a pure tone, and switch to the logarithmic scale to inspect low-frequency content like 50/60 Hz mains hum or bass.

How do I detect clipping or overs?

Watch the dBFS peak meters during playback. dBFS (decibels relative to full scale) tops out at 0 dB — that is the maximum a digital sample can hold. If the meter readout hits 0.0 dB and the bar turns red, samples are pegged at full scale and the audio is likely clipped (distorted). These are sample-peak values, not true-peak (no inter-sample oversampling), so real-world inter-sample overs on lossy or resampled files can sit slightly above 0 dBTP even when the sample peak reads just under 0 dBFS. In the waveform, clipping looks like flat-topped peaks that slam into the top and bottom edges; in the spectrogram it shows up as broadband vertical smears. dBFS and dBTP both describe peak level, whereas LUFS measures perceived loudness over time and is a separate metric.

What are peak meters?

Peak meters show the real-time loudness level in decibels (dB). They help you monitor audio levels and identify clipping. The meters display left and right channels separately for stereo audio.

How do I use A-B loop?

Click the A-B button, then click on the waveform to set point A (start), then click again to set point B (end). The selected section will loop continuously. Click A-B again to cancel.

Can I export the waveform?

Yes! Click the export button to download the waveform as PNG or SVG format. This is useful for documentation, presentations, or sharing your audio analysis.

What is stereo split view?

Stereo split view shows left and right audio channels separately. This helps you analyze stereo imaging, identify channel imbalances, and see differences between channels.

Is my audio file safe?

Absolutely! All audio processing happens directly in your browser. Your audio file is never uploaded to any server. Everything stays private on your device.