The Whetstone benchmark is a synthetic benchmark for evaluating the performance of computers. It was first written in ALGOL 60 in 1972 at the Technical Support Unit of the Department of Trade and Industry (later part of the Central Computer and Telecommunications Agency) in the United Kingdom. It was derived from statistics on program behaviour gathered on the KDF9 computer at NPL National Physical Laboratory, using a modified version of its Whetstone ALGOL 60 compiler. The workload on the machine was represented as a set of frequencies of execution of the 124 instructions of the Whetstone Code. The Whetstone Compiler was built at the Atomic Power Division of the English Electric Company in Whetstone, Leicestershire, England, hence its name. Dr. B.A. Wichman at NPL produced a set of 42 simple ALGOL 60 statements, which in a suitable combination matched the execution statistics.

To make a more practical benchmark Harold Curnow of TSU wrote a program incorporating the 42 statements. This program worked in its ALGOL 60 version, but when translated into FORTRAN it was not executed correctly by the IBM optimizing compiler. Calculations whose results were not output were omitted. He then produced a set of program fragments which were more like real code and which collectively matched the original 124 Whetstone instructions. Timing this program gave a measure of the machine's speed in thousands of Whetstone instructions per second (kWIPS). The Fortran version became the first general purpose benchmark that set industry standards of computer system performance. Further development was carried out by Roy Longbottom, also of TSU/CCTA, who became the official design authority.

In July 2010, the original Algol 60 program ran once again under the Whetstone compiler, 30 years since the shutdown of the last KDF9 machine. The program was executed by a KDF9 emulator.

The benchmark employs 8 test procedures:

The original version only reported comprised parameters used for each test, numeric results produced, and the overall KWIPS performance rating.

In 1978, the program was updated to log running time of each of the tests. As a result, each individual test could report a score. The three floating-point tests each reported one version of the MFLOPS (Millions of Floating Point Operations Per Second) statistic. The rest each reported a MOPS statistic. In 1980, the MOPS of tests 3, 4 and 7 were combined to form the VAX MIPS, a Millions of Integer Instructions Per Second measure calibrated to read the Digital VAX 11/780 as 1 MIPS.

Note that there are other versions of the Whetstone Benchmark available online, some claiming copyright, without reference to CCTA or the design authority.

In conjunction with the undertaking controlled by the Contracts Division, CCTA engineers had responsibility to design and supervise acceptance trials of all UK Government computers and those for centrally funded for Universities and Research Councils, with systems varying from minicomputers to supercomputers. This provided the opportunity to gather verified Whetstone Benchmark results. Other results were obtained via new computer system appraisal activities.