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<title>Non-functional requirement</title>

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<span id="openzim-page-title" class="mw-page-title-main"><span class="mw-page-title-main">Non-functional requirement</span></span>

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In <a href="Systems_engineering" title="Systems engineering">systems engineering</a> and <a href="Requirements_engineering" title="Requirements engineering">requirements engineering</a>, a <b>non-functional requirement</b> (<b>NFR</b>) is a <a href="Requirement" title="Requirement">requirement</a> that specifies criteria that can be used to judge the operation of a system, rather than specific behaviours. They are contrasted with <a href="Functional_requirement" title="Functional requirement">functional requirements</a> that define specific behavior or functions. The plan for implementing <i>functional</i> requirements is detailed in the <a href="Systems_design" title="Systems design">system <i>design</i></a>. The plan for implementing <i>non-functional</i> requirements is detailed in the <a href="Systems_architecture" title="Systems architecture">system <i>architecture</i></a>, because they are usually <a href="Architecturally_significant_requirements" title="Architecturally significant requirements">architecturally significant requirements</a>.<sup id="cite_ref-ASR_Chen_1-0" class="reference"><a href="#cite_note-ASR_Chen-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup>

</p><p>In <a href="Software_architecture" title="Software architecture">software architecture</a>, non-functional requirements are known as "architectural characteristics". Note that synchronous communication between software architectural components entangles them, and they must share the same architectural characteristics.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Definition">Definition</h2></div>

<p>Broadly, functional requirements define what a system is supposed to <i>do</i> and non-functional requirements define how a system is supposed to <i>be</i>. <a href="Functional_requirement" title="Functional requirement">Functional requirements</a> are usually in the form of "system shall do <requirement>", an individual action or part of the system, perhaps explicitly in the sense of a <a href="Function_(mathematics)" title="Function (mathematics)">mathematical function</a>, a <a href="Black_box" title="Black box">black box</a> description input, output, process and control <a href="Functional_model" class="mw-redirect" title="Functional model">functional model</a> or <a href="IPO_model" title="IPO model">IPO model</a>. In contrast, non-functional requirements are in the form of "system shall be <requirement>", an overall property of the system as a whole or of a particular aspect and not a specific function. The system's overall properties commonly mark the difference between whether the development project has succeeded or failed.

</p><p>Non-functional requirements are often called the "<a href="List_of_system_quality_attributes" title="List of system quality attributes">quality attributes</a>" of a system. The <b>emergent properties</b><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>Note 1<span class="cite-bracket">]</span></a></sup> of a system are classified as non-functional requirements. Other terms for non-functional requirements are "qualities", "quality goals", "quality of service requirements", "constraints", "non-behavioral requirements",<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> or "technical requirements".<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> Informally these are sometimes called the "<a href="https://en.wiktionary.org/wiki/ility" class="extiw external" title="wikt:ility">ilities</a>", from attributes like stability and portability. Qualities—that is non-functional requirements—can be divided into two main categories:

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<ol><li>Execution qualities, such as safety, security and usability, which are observable during operation (at run time).</li>

<li>Evolution qualities, such as <a href="Software_testability" title="Software testability">testability</a>, maintainability, extensibility and scalability, which are embodied in the static structure of the system.<sup id="cite_ref-Wiegers13_6-0" class="reference"><a href="#cite_note-Wiegers13-6"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Young01_7-0" class="reference"><a href="#cite_note-Young01-7"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup></li></ol>

<p>It is important to specify non-functional requirements in a specific and measurable way.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-MGUZH_9-0" class="reference"><a href="#cite_note-MGUZH-9"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>

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<div class="mw-heading mw-heading2"><h2 id="Classification_of_non-functional_requirements">Classification of non-functional requirements</h2></div>

<p>Common non-functional classifications, relevant for all types of systems include <sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>

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<ul><li>Performance</li>

<li><a href="Reliability%2C_availability%2C_maintainability_and_safety" title="Reliability, availability, maintainability and safety">Reliability, availability, maintainability and safety</a></li>

<li>Scalability</li>

<li>Testability</li></ul>

<p>Specific type of systems explicitly enumerate categories of non-functional requirements in their standards

</p>

<ul><li>Hardware systems</li>

<li>Embedded systems</li>

<li>Safety-critical systems</li>

<li>Software systems</li></ul>

<div class="mw-heading mw-heading2"><h2 id="Examples">Examples</h2></div>

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<p>A system may be required to present the user with a display of the number of records in a database. This is a functional requirement. How current this number needs to be, is a non-functional requirement. If the number needs to be updated in <a href="Real-time_computing" title="Real-time computing">real time</a>, the system architects must ensure that the system is capable of displaying the record count within an acceptably short interval of the number of records changing.

</p><p>Sufficient network bandwidth may be a non-functional requirement of a system. Other examples include:

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<ul><li><a href="Accessibility" title="Accessibility">Accessibility</a></li>

<li><a href="Adaptability" title="Adaptability">Adaptability</a></li>

<li><a href="Auditability" class="mw-redirect" title="Auditability">Auditability</a> and control</li>

<li><a href="Availability" title="Availability">Availability</a> (see <a href="Service_level_agreement" class="mw-redirect" title="Service level agreement">service level agreement</a>)</li>

<li><a href="Backup" title="Backup">Backup</a></li>

<li><a href="System_capacity" class="mw-redirect" title="System capacity">Capacity</a>, current and forecast</li>

<li><a href="Certification" title="Certification">Certification</a></li>

<li><a href="Compliance_(regulation)" class="mw-redirect" title="Compliance (regulation)">Compliance</a></li>

<li><a href="Configuration_management" title="Configuration management">Configuration management</a></li>

<li><a href="Conformance_testing" title="Conformance testing">Conformance</a></li>

<li>Cost, initial and life-cycle cost</li>

<li><a href="Data_integrity" title="Data integrity">Data integrity</a></li>

<li><a href="Data_retention" title="Data retention">Data retention</a></li>

<li>Dependency on other parties</li>

<li><a href="Software_deployment" title="Software deployment">Deployment</a></li>

<li><a href="Development_environment" class="mw-redirect" title="Development environment">Development environment</a></li>

<li><a href="IT_disaster_recovery" title="IT disaster recovery">Disaster recovery</a></li>

<li><a href="Documentation" title="Documentation">Documentation</a></li>

<li><a href="Durability" title="Durability">Durability</a></li>

<li><a href="Efficiency" title="Efficiency">Efficiency</a> (resource consumption for given load)</li>

<li><a href="Effectiveness" title="Effectiveness">Effectiveness</a> (resulting performance in relation to effort)</li>

<li><a href="Elasticity_(cloud_computing)" class="mw-redirect" title="Elasticity (cloud computing)">Elasticity</a></li>

<li>Emotional factors (like fun or absorbing or has "wow factor")</li>

<li><a href="Environmental_protection" title="Environmental protection">Environmental protection</a></li>

<li><a href="Source_code_escrow" title="Source code escrow">Escrow</a></li>

<li>Ethics</li>

<li>Exploitability</li>

<li><a href="Extensibility" title="Extensibility">Extensibility</a> (adding features, and carry-forward of customizations at next major version upgrade)</li>

<li>Failure management</li>

<li><a href="Fault_tolerance" title="Fault tolerance">Fault tolerance</a> (e.g. operational system monitoring, measuring, and management)</li>

<li>Flexibility (e.g. to deal with future changes in requirements)</li>

<li>Footprint reduction - reduce the exe files size</li>

<li><a href="System_integration" title="System integration">Integrability</a> (e.g. ability to integrate components)</li>

<li><a href="Internationalization_and_localization" title="Internationalization and localization">Internationalization and localization</a></li>

<li><a href="Interoperability" title="Interoperability">Interoperability</a></li>

<li>Legal and <a href="Software_license_agreement" class="mw-redirect" title="Software license agreement">licensing</a> issues or patent-infringement-avoidability</li>

<li><a href="Maintainability" title="Maintainability">Maintainability</a> (e.g. <a href="Mean_time_to_repair" title="Mean time to repair">mean time to repair</a> – MTTR)</li>

<li>Management</li>

<li>Memory optimization</li>

<li>Modifiability</li>

<li><a href="Network_topology" title="Network topology">Network topology</a></li>

<li><a href="Open_source" title="Open source">Open source</a></li>

<li><a href="Operability" title="Operability">Operability</a></li>

<li><a href="Computer_performance" title="Computer performance">Performance</a> / response time (<a href="Performance_engineering" title="Performance engineering">performance engineering</a>)</li>

<li><a href="Platform_(computing)" class="mw-redirect" title="Platform (computing)">Platform</a> compatibility</li>

<li><a href="Privacy" title="Privacy">Privacy</a> (compliance to <a href="Privacy_law" title="Privacy law">privacy laws</a>)</li>

<li><a href="Software_portability" title="Software portability">Portability</a></li>

<li><a href="Quality_(business)" title="Quality (business)">Quality</a> (e.g. faults discovered, faults delivered, fault removal <a href="Efficacy" title="Efficacy">efficacy</a>)</li>

<li><a href="Computer_programming#Readability_of_source_code" title="Computer programming">Readability</a></li>

<li><a href="Reliability_engineering" title="Reliability engineering">Reliability</a> (e.g. <a href="Mean_time_between_failures" title="Mean time between failures">mean time between/to failures</a> – MTBF/MTTF)</li>

<li>Reporting</li>

<li><a href="Resilience_(network)" class="mw-redirect" title="Resilience (network)">Resilience</a></li>

<li>Resource constraints (processor speed, memory, disk space, network bandwidth, etc.)</li>

<li><a href="Response_Time" class="mw-redirect" title="Response Time">Response time</a></li>

<li><a href="Reusability" title="Reusability">Reusability</a></li>

<li><a href="Robustness_(computer_science)" title="Robustness (computer science)">Robustness</a></li>

<li><a href="Safety" title="Safety">Safety</a> or <a href="Factor_of_safety" title="Factor of safety">factor of safety</a></li>

<li><a href="Scalability" title="Scalability">Scalability</a> (horizontal, vertical)</li>

<li><a href="Computer_security" title="Computer security">Security</a> (cyber and physical)</li>

<li>Software, tools, standards etc. <a href="Backward_compatibility" title="Backward compatibility">Compatibility</a></li>

<li><a href="Stability_model" title="Stability model">Stability</a></li>

<li><a href="Serviceability_(computer)" title="Serviceability (computer)">Supportability</a></li>

<li><a href="Software_testability" title="Software testability">Testability</a></li>

<li><a href="Throughput" class="mw-redirect" title="Throughput">Throughput</a></li>

<li><a href="Transparency_(behavior)" title="Transparency (behavior)">Transparency</a></li>

<li><a href="Usability" title="Usability">Usability</a> (human factors) by target user community</li>

<li><a href="Volume_testing" title="Volume testing">Volume testing</a></li></ul>

</div>

<li><a href="CISQ" title="CISQ">Consortium for IT Software Quality</a></li>

<li><a href="FURPS" title="FURPS">FURPS</a></li>

<li><a href="Requirements_analysis" title="Requirements analysis">Requirements analysis</a></li>

<li><a href="Usability_requirements" class="mw-redirect" title="Usability requirements">Usability requirements</a></li>

<li><a href="Non-Functional_Requirements_framework" class="mw-redirect" title="Non-Functional Requirements framework">Non-Functional Requirements framework</a></li>

<li><a href="Architecturally_Significant_Requirements" class="mw-redirect" title="Architecturally Significant Requirements">Architecturally Significant Requirements</a></li>

<li><a href="SNAP_Points" title="SNAP Points">SNAP Points</a></li></ul>

<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>

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</style><cite id="CITEREFChenAli_BabarNuseibeh2013" class="citation journal cs1">Chen, Lianping; Ali Babar, Muhammad; Nuseibeh, Bashar (2013). "Characterizing Architecturally Significant Requirements". <i>IEEE Software</i>. <b>30</b> (2): <span class="nowrap">38–</span>45. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMS.2012.174">10.1109/MS.2012.174</a>. <a href="Hdl_(identifier)" class="mw-redirect" title="Hdl (identifier)">hdl</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://hdl.handle.net/10344%2F3061">10344/3061</a></span>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:17399565">17399565</a>.</cite></span>

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<li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><cite id="CITEREFRichardsFord2020" class="citation book cs1">Richards, Mark; Ford, Neal (2020). <i>Fundamentals of Software Architecture: An Engineering Approach</i>. O'Reilly Media, Incorporated. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-1492043454</bdi>.</cite></span>

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<li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><cite id="CITEREFStellmanGreene2005" class="citation book cs1">Stellman, Andrew; Greene, Jennifer (2005). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20150209011617/http://www.stellman-greene.com/aspm/"><i>Applied Software Project Management</i></a>. <a href="O'Reilly_Media" title="O'Reilly Media">O'Reilly Media</a>. p. 113. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-596-00948-9</bdi>. Archived from <a rel="nofollow" class="external text" href="http://www.stellman-greene.com/aspm/">the original</a> on 2015-02-09.</cite></span>

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<li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><cite id="CITEREFAmbler" class="citation web cs1">Ambler, Scott. <a rel="nofollow" class="external text" href="http://agilemodeling.com/artifacts/technicalRequirement.htm">"Technical (Non-Functional) Requirements: An Agile Introduction"</a>. <i>Agile Modelling</i>. Ambysoft Inc<span class="reference-accessdate">. Retrieved <span class="nowrap">5 October</span> 2018</span>.</cite></span>

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<li id="cite_note-Wiegers13-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-Wiegers13_6-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFWiegersBeatty2013" class="citation book cs1">Wiegers, Karl; Beatty, Joy (2013). <i>Software Requirements, Third Edition</i>. Microsoft Press. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-7356-7966-5</bdi>.</cite></span>

</li>

<li id="cite_note-Young01-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-Young01_7-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFYoung2001" class="citation book cs1">Young, Ralph R. (2001). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/unset0000unse_g5k2"><i>Effective Requirements Practices</i></a></span>. Addison-Wesley. <a href="ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <bdi>978-0-201-70912-4</bdi>.</cite></span>

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<li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><cite id="CITEREFZimmermannStocker2021" class="citation book cs1">Zimmermann, Olaf; Stocker, Mirko (2021). <a rel="nofollow" class="external text" href="https://leanpub.com/dpr"><i>Design Practice Repository</i></a>. LeanPub.</cite></span>

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<li id="cite_note-MGUZH-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-MGUZH_9-0">^</a></b></span> <span class="reference-text"><cite id="CITEREFGlinz2008" class="citation journal cs1">Glinz, Martin (2008). <a rel="nofollow" class="external text" href="https://www.zora.uzh.ch/id/eprint/7375/10/ieeesoftwaregetPDFV.pdf">"A Risk-Based, Value-Oriented Approach to Quality Requirements"</a> <span class="cs1-format">(PDF)</span>. <i>IEEE Software</i>. <b>25</b> (2): <span class="nowrap">34–</span>41. <a href="Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMS.2008.31">10.1109/MS.2008.31</a>. <a href="S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:19015424">19015424</a>.</cite></span>

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<li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://sebokwiki.org/wiki/Systems_Engineering_and_Quality_Attributes">"Systems Engineering and Quality Attributes KA"</a>. <i>sebokwiki.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">24 May</span> 2025</span>.</cite></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2></div>

<li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text">See definition in <a rel="nofollow" class="external text" href="https://sebokwiki.org/wiki/Emergent_Property_(glossary)">SeBoK Glossary</a></span>

</li>

</ol></div></div>

<div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div>

<ul><li><cite id="CITEREFPetter_L._H._Eide2005" class="citation citeseerx cs1">Petter L. H. Eide (2005). "Quantification and Traceability of Requirements". <a href="CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.95.6464">10.1.1.95.6464</a></span>.</cite></li>

<li><cite id="CITEREFDalbey" class="citation web cs1">Dalbey, John. <a rel="nofollow" class="external text" href="http://www.csc.calpoly.edu/~jdalbey/SWE/QA/nonfunctional.html">"Nonfunctional Requirements"</a>. <i>Csc.calpoly.edu</i><span class="reference-accessdate">. Retrieved <span class="nowrap">3 October</span> 2017</span>.</cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20110724131731/http://www.cs.umb.edu/~jxs/pub/scc.pdf">"Modeling Non-Functional Aspects in Service Oriented Architecture"</a> <span class="cs1-format">(PDF)</span>. <i>Cs.umb.edu</i>. Archived from <a rel="nofollow" class="external text" href="http://www.cs.umb.edu/~jxs/pub/scc.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 24 July 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">3 October</span> 2017</span>.</cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.methodsandtools.com/archive/archive.php?id=113">"Non-Functional Requirements: Do User Stories Really Help?"</a>. <i>Methodsandtools.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">3 October</span> 2017</span>.</cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://it-cisq.org/non-functional-requirements-be-here">"Non-Functional Requirements Be Here - CISQ - Consortium for IT Software Quality"</a>. <i>it-cisq.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">3 October</span> 2017</span>.</cite></li>

<li><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://ozimmer.ch/practices/2020/11/19/ExtraExtraReadAllboutIt.html">""Do Software Architectures Meet Extra-Functional or Non-Functional Requirements?""</a>. 19 November 2020.</cite></li></ul>

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</style><div id="Software_quality258" style="font-size:114%;margin:0 4em"><a href="Software_quality" title="Software quality">Software quality</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Qualities</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;">Internal</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a href="Maintainability#Software_engineering" title="Maintainability">Maintainability</a></li>

<li><a href="Flexibility_(engineering)" title="Flexibility (engineering)">Flexibility</a></li>

<li><a href="Software_portability" title="Software portability">Portability</a></li>

<li><a href="Reusability" title="Reusability">Reusability</a></li>

<li><a href="Computer_programming#Readability_of_source_code" title="Computer programming">Readability</a></li>

<li><a href="Scalability" title="Scalability">Scalability</a></li>

<li><a href="Software_testability" title="Software testability">Testability</a></li>

<li><a href="Understandability" class="mw-redirect" title="Understandability">Understandability</a></li>

<li><a href="Loose_coupling" title="Loose coupling">Loose coupling</a></li>

<li><a href="Orthogonality_(programming)" title="Orthogonality (programming)">Orthogonality</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%;font-weight:normal;">External</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Usability" title="Usability">Usability</a></li>

<li><a href="Reliability_engineering" title="Reliability engineering">Reliability</a></li>

<li><a href="Adaptability" title="Adaptability">Adaptability</a></li>

<li><a href="Correctness_(computer_science)" title="Correctness (computer science)">Correctness</a></li>

<li><a href="Accuracy_and_precision" title="Accuracy and precision">Accuracy</a></li>

<li><a href="Algorithmic_efficiency" title="Algorithmic efficiency">Efficiency</a></li>

<li><a href="Robustness_(computer_science)" title="Robustness (computer science)">Robustness</a></li>

<li><a href="Software_development_security" class="mw-redirect" title="Software development security">Security</a></li>

<li><a href="Software_system_safety" class="mw-redirect" title="Software system safety">Safety</a></li></ul>

</div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Standards and lists</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em">

<li><a class="mw-selflink-fragment" href="#Examples">Non-functional requirements</a></li>

<li><a href="List_of_system_quality_attributes" title="List of system quality attributes">List of system quality attributes</a></li></ul>

</div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Processes</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em">

<ul><li><a href="Software_quality_management" title="Software quality management">Software quality management</a></li>

<li><a href="Software_quality_control" title="Software quality control">Software quality control</a></li>

<li><a href="Software_quality_assurance" title="Software quality assurance">Software quality assurance</a></li></ul>

</div></td></tr><tr><td class="navbox-abovebelow" colspan="2" style="font-weight:bold;"><div>

<li><span class="noviewer" typeof="mw:File"><span title="Commons page"></span></span> <a href="https://commons.wikimedia.org/wiki/Category:Software_quality" class="extiw external" title="commons:Category:Software quality">Commons</a></li></ul>

</div></td></tr></tbody></table></div>

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