Skip to main content

system requirements specification

system requirements specification A detailed statement of the effects that a system is required to achieve. A good specification gives a complete statement of what the system is to do, without making any commitment as to how the system is to do it: it constrains only the externally observable behavior and omits any design or implementation bias.

A system requirements specification is normally produced in response to a user requirements specification or other expression of requirements, and is then used as the basis for system design. The system requirements specification typically differs from the expression of requirements in both scope and precision: the latter may cover both the envisaged system and the environment in which it will operate, but may leave many broad concepts unrefined. Traditionally, system requirements specifications took the form of natural-language documents. However, both the need for precision and problems with the increasing size of specification documents have led to the development of more formal notations. These are capable of being mathematically manipulated so as to show that the system as designed and implemented actually meets the specification. This may be especially important in connection with safety-critical systems.

A system requirements specification may also be used in contract negotiations during and after the purchase of the system, which must meet the specifications that the contractor has agreed to accept. This is especially important where the purchaser sets out the requirements in terms of a range of functions and performance levels that the contractor commits to supplying and meeting, rather than as an inventory of components (hardware and software) that the contractor undertakes to supply.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"system requirements specification." A Dictionary of Computing. . 21 Apr. 2019 <>.

"system requirements specification." A Dictionary of Computing. . (April 21, 2019).

"system requirements specification." A Dictionary of Computing. . Retrieved April 21, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.