Periodicity Finder

Local · No API Cost

Finds the dominant repeating cycle in a series or event log via FFT — real technique, no ML model

Paste a series or a list of event times. One value per line — plain numbers (treated as evenly spaced), or timestamps (ISO, a date, or a unix epoch). It finds the strongest repeating cycle via an FFT. Everything runs in your browser; nothing is uploaded.

Data — one value per line (0 lines)