PNGolin computes binned estimators for the real-space three-dimensional power spectrum, bispectrum, and trispectrum from cosmological density fields; it places particular emphasis on trispectrum estimators. The code includes Cython-accelerated routines for constructing Fourier-space power spectrum meshes, selecting discrete modes in specified wave number ranges, and computing auto and cross power spectra, bispectra, and trispectra with configurable binning, box size, and threading options. The software can incorporate fiducial power spectra via interpolators or precomputed meshes to evaluate disconnected contributions and normalizations for trispectrum estimators. PNGolin depends on Cython and pyFFTW (ascl:2109.009) and can interoperate with external tools such as Pylians (ascl:1811.008) for reading input density fields.