The DFT of a real sequence of numbers will be a sequence of complex numbers of the same length which can be calculated using discrete Fourier transform calculator. The DFT converts a finite sequence of equally-spaced samples of a function into an equivalent-length sequence of equally-spaced samples of the discrete-time Fourier transform (DTFT), which is a complex-valued function of frequency. Use this online Fourier series DTF calculator to perform discrete Fourier transformation calculation.