# Understanding Error Suggestion

## In brief

Goal
  Users get suggestions on how to resolve errors.
What to do
  Where errors are detected, suggest known ways to correct them.
Why it's important
  People can address errors faster and with reduced effort.

## Intent of Error Suggestion

The intent of this Success Criterion is to ensure that users receive appropriate suggestions for correction of an input error if it is possible. The definition of "input error" says that it is "information provided by the user that is not accepted" by the system. Some examples of information that is not accepted include information that is required but omitted by the user and information that is provided by the user but that falls outside the required data format or allowed values.

Success Criterion 3.3.1 provides for notification of errors. However, persons with cognitive limitations may find it difficult to understand how to correct the errors. People with visual disabilities may not be able to figure out exactly how to correct the error. In the case of an unsuccessful form submission, users may abandon the form because they may be unsure of how to correct the error even though they are aware that it has occurred.

The content author may provide the description of the error, or the user agent may provide the description of the error based on technology-specific, programmatically determined information.

## Benefits of Error Suggestion

- Providing information about how to correct input errors allows users who have learning disabilities to fill in a form successfully.
- Users who are blind or have impaired vision understand more easily the nature of the input error and how to correct it.
- People with motion impairment can reduce the number of times they need to change an input value.

## Examples of Error Suggestion

Additional Help for Correcting An Input Error
  The result of a form that was not successfully submitted describes an input error in place in the page along with the correct input and offers additional help for the form field that caused the input error.
Suggestions from a Limited Set of Values

  An input field requires that a month name be entered. If the user enters "12," suggestions for correction may include:

  - A list of the acceptable values, e.g., "Choose one of: January, February, March, April, May, June, July, August, September, October, November, December."
  - The conversion of the input data interpreted as a different month format, e.g., "Do you mean 'December'?"

## Resources for Error Suggestion

## Techniques for Error Suggestion

In some cases, more than one of these situations may apply. For example, when a mandatory field also requires the data to be in a specific format.

### Sufficient Techniques for Error Suggestion

#### Situation A: If information for a field is required to be in a specific data format:

- Providing a text description when user input falls outside the required format or values
- Providing suggested correction text

#### Situation B: Information provided by the user is required to be one of a limited set of values:

- Providing a text description when the user provides information that is not in list of allowed values
- Providing suggested correction text

### Additional Techniques (Advisory) for Error Suggestion

- G139: Creating a mechanism that allows users to jump to errors
- Providing success feedback when data is submitted successfully

#### Client-Side Scripting Techniques (Advisory)

- Providing client-side validation and alert
- Providing client-side validation and adding error text via the DOM

### Failures for Error Suggestion