In the presented paper, the analysis of harmonics is done in loads particularly in non-linear loads like welding machine, induction motor, dc drives and ac drives computers, printers, TVs, servers. The harmonics reduces the power quality of the system and machine efficiency also. The harmonics are analysed by making the use of fast flourier transform technique. The harmonic analyser is used to detect the presence of harmonics in the electrical load and if detected than shows the presence of harmonics in the form of voltage and current waveform in the harmonic analyser which is capable of detecting harmonics up to ninety-nine level.