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Understanding SC 3.3.2:Labels or Instructions (Level A)

In Brief

Goal
Users know what information to enter.
What to do
Provide labels or instructions for inputs.
Why it's important
Everyone, especially those with cognitive disabilities, will know how to respond.

Intent

The intent of this Success Criterion is to have content authors present instructions or labels that identify the controls in a form so that users know what input data is expected. In the case of radio buttons, checkboxes, comboboxes, or similar controls that provide users with options, each option must have an appropriate label so that users know what they are actually selecting. Instructions or labels may also specify data formats for data entry fields, especially if they are out of the customary formats or if there are specific rules for correct input. Content authors may also choose to make such instructions available to users only when the individual control has focus especially when instructions are long and verbose.

The intent of this Success Criterion is not to clutter the page with unnecessary information but to provide important cues and instructions that will benefit people with disabilities. Too much information or instruction can be just as harmful as too little. The goal is to make certain that enough information is provided for the user to accomplish the task without undue confusion or navigation.

This Success Criterion does not require that labels or instructions be correctly marked up, identified, or associated with their respective controls - this aspect is covered separately by 1.3.1: Info and Relationships. It is possible for content to pass this Success Criterion (providing relevant labels and instructions) while failing Success Criterion 1.3.1 (if the labels or instructions aren't correctly marked up, identified, or associated).

Further, this Success Criterion does not take into consideration whether or not alternative methods of providing an accessible name or description for form controls and inputs has been used - this aspect is covered separately by 4.1.2: Name, Role and Value. It is possible for controls and inputs to have an appropriate accessible name or description (e.g. using aria-label="...") and therefore pass Success Criterion 4.1.2, but to still fail this Success Criterion (if the labels or instructions aren't presented to all users, not just those using assistive technologies).

This Success Criterion does not apply to links or other controls (such as an expand/collapse widget, or similar interactive components) that are not associated with data entry.

While this Success Criterion requires that controls and inputs have labels or instructions, whether or not labels (if used) are sufficiently clear or descriptive is covered separately by 2.4.6: Headings and Labels.

Benefits

  • Providing labels and instructions (including examples of expected data formats) helps all users - but particularly those with cognitive, language, and learning disabilities - to enter information correctly.
  • Providing labels and instructions (including identification of required fields) can prevent users from making incomplete or incorrect form submissions, which prevents users from having to navigate once more through a page/form in order to fix submission errors.

Examples

  • A field which requires the user to enter the two character abbreviation for a US state has a link next to it which will popup an alphabetized list of state names and the correct abbreviation.
  • A field for entering a date contains initial text which indicates the correct format for the date.
  • To enter their name, users are provided with two separate text fields. Rather than having a single label "Name" (which would appear to leave the second text field unlabelled), each field is given an explicit label - "Given Name" and "Family Name".
  • A U.S. phone number separates the area code, exchange, and number into three fields. Parentheses surround the area code field, and a dash separates the exchange and number fields. While the punctuation provides visual clues to those familiar with the U.S. telephone number format, the punctuation is not sufficient to label the fields. The single "Phone number" label also cannot label all three fields. To address this, the three fields are grouped in a fieldset with the legend "Phone number". Visual labels for the fields (beyond the punctuation) cannot be provided in the design, so invisible labels are provided with the "title" attribute to each of the three fields. The value of this attribute for the three fields are, respectively, "Area Code", "Exchange", and "Number".

Techniques

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

Note

The techniques at the end of the above list should be considered "last resort" and only used when the other techniques cannot be applied to the page. The earlier techniques are preferred because they increase accessibility to a wider user group.

Advisory Techniques

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

Failures

The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

Key Terms

ascii art

picture created by a spatial arrangement of characters or glyphs (typically from the 95 printable characters defined by ASCII)

assistive technology

hardware and/or software that acts as a user agent, or along with a mainstream user agent, to provide functionality to meet the requirements of users with disabilities that go beyond those offered by mainstream user agents

Note

Functionality provided by assistive technology includes alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible).

Note

Assistive technologies often communicate data and messages with mainstream user agents by using and monitoring APIs.

Note

The distinction between mainstream user agents and assistive technologies is not absolute. Many mainstream user agents provide some features to assist individuals with disabilities. The basic difference is that mainstream user agents target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The mainstream user agent may provide important functionality to assistive technologies like retrieving Web content from program objects or parsing markup into identifiable bundles.

content

information and sensory experience to be communicated to the user by means of a user agent, including code or markup that defines the content's structure, presentation, and interactions

human language

language that is spoken, written or signed (through visual or tactile means) to communicate with humans

Note

See also sign language.

label

text or other component with a text alternative that is presented to a user to identify a component within Web content

Note

A label is presented to all users whereas the name may be hidden and only exposed by assistive technology. In many (but not all) cases the name and the label are the same.

Note

The term label is not limited to the label element in HTML.

name

text by which software can identify a component within Web content to the user

Note

The name may be hidden and only exposed by assistive technology, whereas a label is presented to all users. In many (but not all) cases, the label and the name are the same.

Note

This is unrelated to the name attribute in HTML.

non-text content

any content that is not a sequence of characters that can be programmatically determined or where the sequence is not expressing something in human language

Note

This includes ASCII Art (which is a pattern of characters), emoticons, leetspeak (which uses character substitution), and images representing text

presentation

rendering of the content in a form to be perceived by users

programmatically determined

determined by software from author-supplied data provided in a way that different user agents, including assistive technologies, can extract and present this information to users in different modalities

sign language

a language using combinations of movements of the hands and arms, facial expressions, or body positions to convey meaning

structure
  1. The way the parts of a Web page are organized in relation to each other; and
  2. The way a collection of Web pages is organized
text

sequence of characters that can be programmatically determined, where the sequence is expressing something in human language

text alternative

Text that is programmatically associated with non-text content or referred to from text that is programmatically associated with non-text content. Programmatically associated text is text whose location can be programmatically determined from the non-text content.

Note

Refer to Understanding Text Alternatives for more information.

user agent

any software that retrieves and presents Web content for users

web page

a non-embedded resource obtained from a single URI using HTTP plus any other resources that are used in the rendering or intended to be rendered together with it by a user agent

Note

Although any "other resources" would be rendered together with the primary resource, they would not necessarily be rendered simultaneously with each other.

Note

For the purposes of conformance with these guidelines, a resource must be "non-embedded" within the scope of conformance to be considered a Web page.

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