Joerg's FXT Page - Source code and links for many different FFT implementations and related information.FFT Page - Links and various Fortran FFT implementations.
Notes on the FFT - Overview of FFT literature, with many references.
Fast Fourier Transforms - Contains Fast Fourier Transform source code (C, C++, Pascal), tutorial, and math theory.
benchFFT - Benchmark comparing speeds of many FFT codes. Results from many machines, and code to run it yourself.
FFT Links - Links to many sources of FFT code and information.
FFTW - Fast free C FFT library; includes multi-dimensional, real-complex, and parallel transforms.
A Short Demonstration Version of the FFT Source Code in Fortran - Source Code in Fortran for FFT from "Programs for Digital Signal Processing", 1979, IEEE Press, ISBN 0-87942-127-4. The book is necessary to use and understand these source code listings.
Jens J. Nielsen's home page - Arbitrary length FFT C-source, 3D gravity simulator, quantization of FIR filter coefficients.
