High Quality Content by WIKIPEDIA articles! The Fletcher checksum is an algorithm for computing a position-dependent checksum devised by John G. Fletcher at Lawrence Livermore Labs in the late 1970s. A description of the algorithm and an analysis of the performance characteristics of a particular implementation were published in the IEEE Transactions on Communications in January 1982. The objective of the Fletcher checksum was to provide error-detection properties approaching those of a cyclic redundancy check but with the lower computational effort associated with summation techniques.