Error Prevention (Legal, Financial, Data)

About

Version:	WCAG 2.0 and up
Number:	3.3.4
Level:	AA
Applicability:	Forms
Requirement:	For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following is true: Reversible Submissions are reversible. Checked Data entered by the user is checked for input errors and the user is provided an opportunity to correct them. Confirmed A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.
Guidance:	Understanding Success Criterion 3.3.4 How to meet Success Criterion 3.3.4
Techniques:	G98: Providing the ability for the user to review and correct answers before submitting G99: Providing the ability to recover deleted information G155: Providing a checkbox in addition to a submit button G164: Providing a stated time within which an online request (or transaction) may be amended or canceled by the user after making the request G168: Requesting confirmation to continue with selected action

Purpose

The purpose of this success criterion is to ensure that users have a chance to correct errors in their data and/or review the data before it is submitted to a server that would store it. Alternatively, users need to be provided the ability to undo their submission.

How to Meet

This success criterion will most commonly only apply to tests, as digital publications do not typically collect legal and financial data.

Digital textbooks may sometimes contain tests that are submitted to a remote server (e.g., a school course portal). In these cases, authors need to either validate the input and allow users to correct any errors before submitting or provide users with the change to confirm their input. Ideally, both options would be provided.

If undoing a submission is the only way to meet this criterion, finding an alternative means than the publication is recommended. For example, a user might be able to undo their submission from a course portal until the duration they have been given to complete the test expires.

Note that the success criterion only applies if the data is transferred and stored on a remote server. Quizzes and other embedded tests that only run within a digital publication are not subject to these requirements.

Additional Information

The following knowledge base pages provide more information about how to address this success criterion for publishing content:

Input Validation