Тестирование юзабилити в пользовательском интерфейсе.

Technique in user centered interaction design
Usability testing is a technique used in user centered interaction design to evaluate a product by testing it on users. This can be seen as an irreplaceable usability practice, since it gives direct input on how real users use the system. It is more concerned with the design intuitiveness of the product and tested with users who have no prior exposure to it. Such testing is paramount to the success of an end product as a fully functioning application that creates confusion amongst its users will not last for long. This is in contrast with usability inspection methods where experts use different methods to evaluate a user interface without involving users. Usability testing focuses on measuring a human made product's capacity to meet its intended purposes. Examples of products that commonly benefit from usability testing are food, consumer products, websites or web applications, computer interfaces, documents, and devices. Usability testing measures the usability, or ease of use, of a specific object or set of objects, whereas general human–computer interaction studies attempt to formulate universal principles.

Simply gathering opinions on an object or a document is market research or qualitative research rather than usability testing. Usability testing usually involves systematic observation under controlled conditions to determine how well people can use the product. However, often both qualitative research and usability testing are used in combination, to better understand users' motivations/perceptions, in addition to their actions. Rather than showing users a rough draft and asking, "Do you understand this? ", usability testing involves watching people trying to use something for its intended purpose. For example, when testing instructions for assembling a toy, the test subjects should be given the instructions and a box of parts and, rather than being asked to comment on the parts and materials, they should be asked to put the toy together. Instruction phrasing, illustration quality, and the toy's design all affect the assembly process.

Setting up a usability test involves carefully creating a scenario, or a realistic situation, wherein the person performs a list of tasks using the product being tested while observers watch and take notes (dynamic verification). Several other test instruments such as scripted instructions, paper prototypes, and pre and post test questionnaires are also used to gather feedback on the product being tested (static verification). For example, to test the attachment function of an e mail program, a scenario would describe a situation where a person needs to send an e mail attachment, and asking them to undertake this task. The aim is to observe how people function in a realistic manner, so that developers can identify the problem areas and fix them. Techniques popularly used to gather data during a usability test include think aloud protocol, co discovery learning and eye tracking.

Hallway testing, also known as guerrilla usability, is a quick and cheap method of usability testing in which people — such as those passing by in the hallway—are asked to try using the product or service. This can help designers identify "brick walls", problems so serious that users simply cannot advance, in the early stages of a new design. Anyone but project designers and engineers can be used (they tend to act as "expert reviewers" because they are too close to the project). This type of testing is an example of convenience sampling and thus the results are potentially biased.

Similar to expert reviews, automated expert reviews provide usability testing but through the use of programs given rules for good design and heuristics. Though an automated review might not provide as much detail and insight as reviews from people, they can be finished more quickly and consistently. The idea of creating surrogate users for usability testing is an ambitious direction for the artificial intelligence community.

In web development and marketing, A/B testing or split testing is an experimental approach to web design (especially user experience design), which aims to identify changes to web pages that increase or maximize an outcome of interest (e. g., click through rate for a banner advertisement). As the name implies, two versions (A and B) are compared, which are identical except for one variation that might impact a user's behavior. Version A might be the one currently used, while version B is modified in some respect. For instance, on an e commerce website the purchase funnel is typically a good candidate for A/B testing, as even marginal improvements in drop off rates can represent a significant gain in sales. Significant improvements can be seen through testing elements like copy text, layouts, images and colors. Multivariate testing or bucket testing is similar to A/B testing but tests more than two versions at the same time.

Usability testing has been a formal subject of academic instruction in different disciplines. Usability testing is important to composition studies and online writing instruction (OWI). Scholar Collin Bjork argues that usability testing is "necessary but insufficient for developing effective OWI, unless it is also coupled with the theories of digital rhetoric."

Survey products include paper and digital surveys, forms, and instruments that can be completed or used by the survey respondent alone or with a data collector. Usability testing is most often done in web surveys and focuses on how people interact with survey, such as navigating the survey, entering survey responses, and finding help information. Usability testing complements traditional survey pretesting methods such as cognitive pretesting (how people understand the products), pilot testing (how will the survey procedures work), and expert review by a subject matter expert in survey methodology. In translated survey products, usability testing has shown that "cultural fitness" must be considered in the sentence and word levels and in the designs for data entry and navigation, and that presenting translation and visual cues of common functionalities (tabs, hyperlinks, drop down menus, and URLs) help to improve the user experience.