Labels or Instructions (Level A)

For any element that requires user input or action, provide concise labels and/or instructions.

What you need to know

The purpose of this success criterion is to make it easy to understand what data input or action is being asked for. For example, rather than simply labeling a form field as “email,” indicate “your preferred email for receiving our newsletter.”
Every element that allows for user input should have clear, concise, descriptive labels and, where applicable, instructions.
A label could be “First Name.”
An instruction could be “All fields marked with an * are required.”
It’s very important not to make labels or instructions too long or complex. This slows down the process of inputting data.

Assign a visible label for every form field or area of user engagement/control.
Programmatically associate labels with the appropriate form fields.
Don’t overextend instructions–a few words should be enough.
Provide examples of expected input formats or structure data input so that the expected format is entered.
Make very clear which fields are required.

Check out “Provide Accessible Labels and Instructions” from Harvard University – Digital Accessibility for more information about this success criterion.