FFT Tool

The online fft tool provides browser-based computation of the discrete Fourier transform for time-domain data. It targets engineers, researchers, students, and hobbyists who need to analyze spectral content without installing software. Typical use cases include analyzing audio recordings, sensor traces, vibration data, and lab measurements when quick, reproducible spectra are required.
Conceptually, the tool accepts time-domain samples, applies an optional window to reduce leakage, performs an N-point FFT, and returns frequency-domain representations. The frequency axis is defined as f_k = k·Fs/N, where Fs is the sample rate. Outputs include magnitude, phase, and optionally power spectra; there is support for linear or decibel scaling.
The value proposition lies in accessibility, speed, and data portability. Users can paste data, upload CSV, or provide real-valued or complex inputs, compute results in seconds, and export as CSV or JSON for reproducibility. Real-time feedback and multiple transform lengths facilitate quick comparisons across several signals and conditions.
Core features include: input validation; window options (Hann, Hamming, Blackman); zero-padding; real/complex input; multiple channels; export of spectra; optional DC removal; straightforward interpretation of magnitude and phase; no hidden dependencies; suitable for educational demos, signal processing research, and engineering workflows.