PPolySim OS

DFT Spectrum Analysis

A tangle of overlapping waves hides simple frequencies inside. Watch the DFT untangle a messy signal into sharp spectral peaks.

DFT Spectrum AnalysisLive

Controls

Presets

The Discrete Fourier Transform decomposes a signal into its constituent frequencies. A messy time-domain wave becomes clean peaks in the spectrum — the mathematics behind audio equalizers, MRI, and Wi-Fi. Educational tool.

▶ Run in Python

Data Inspector

Peak 15 cycles
Peak 212 cycles
Resolution0.008 cyc/sample

Governing equation

Reading this result: Two clean sinusoids produce two crisp peaks at their frequencies; peak height tracks amplitude, which is exactly how an equalizer reads a signal.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

or unlock everything with Pro →
★ Sign in to save this setup
Save your tuned setup, or drop this simulation into your own site, docs, or course page.

How it works

The Discrete Fourier Transform expresses a sampled signal as a sum of sinusoids, revealing which frequencies are present and how strong. It powers spectrum analyzers, audio equalizers, image compression, and countless measurement tools. Educational tool.

Ask the AI about this model

The math, the assumptions, real-world uses, or a code translation — explained for this exact simulation.

More Signals simulations

Frequently asked questions

Is this dft spectrum analyzer tool really free?
Yes. DFT Spectrum Analysis 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.