See sound as a picture. A real short-time Fourier transform turns a 1D signal into a time–frequency heatmap, right in your browser.
Spectrogram StudioLive
STFT time–frequency analysis
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Signal
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A real short-time Fourier transform: the signal is sliced into overlapping windows, each Fourier-transformed, and stacked into a time–frequency heatmap.
Reading this result: A 256-point window balances the two: Δf = 15.6 Hz in frequency against 64 ms in time. Widen it for sharper tones, narrow it to pin down fast transients — you cannot sharpen both at once.
Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.
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How it works
A spectrogram slides a tapered window along the signal, takes a real radix-2 FFT of each slice, and stacks the magnitudes (in dB) into a heatmap — time on the x-axis, frequency on the y-axis, brightness as energy. Sweep the window size to feel the core tradeoff of the STFT: a long window resolves close tones but blurs fast events, while a short window pins down transients but smears frequency. This is the same analysis behind speech recognition, music visualizers, radar, and vibration diagnostics.
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Ask the AI about this model
The math, the assumptions, real-world uses, or a code translation — explained for this exact simulation.
Is this spectrogram STFT time frequency tool really free?▾
Yes. Spectrogram runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?▾
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.