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When filling in a form, it is important to provide the minimum amount of information for the form to function. These fields are known as mandatory or required fields. The best way to indicate required fields is to include the text “required” or “mandatory” in the form field’s visible text label. Another option is to use a (typically red) asterisk in the visible text label, which is a well-established convention. However, it is still recommended to include a note at the beginning of the form to explain the meaning of the asterisk.
The most unambiguous way to indicate information that users need to provide is to include the text “required” or “mandatory” in the form field's visible text label.
Screen reader users may find asterisks less meaningful, as they have to listen for the ambiguous word “star.” To improve accessibility, it is suggested to provide alternative text or explanation for the visual indicator of required fields to ensure that all users can understand its meaning.
Yet with or without such an explanation, asterisks provide a very visual solution and can be less meaningful to screen reader users, who must listen out for the ambiguous word “star.”