Labeling Required and Optional Form Fields Test

Form completion rate

Compare successful submissions among visitors who see the form.

• Required-field error rateTrack errors caused by missing required fields or invalid entries.
• Form completion timeCompare time from form start to successful submission.
• Field-level abandonmentReview the last field interacted with by visitors who leave without completing the form.
• Form-related support rateTrack support requests about filling in the form or understanding a field.

• LabelsUse one consistent rule to mark each field as required or optional.
• Keep constantKeep field count, order and validation rules unchanged.
• ErrorsTrack errors caused by required fields left blank.
• MobileMake sure labels do not truncate field names on narrow screens.
• Separate comparisonsTest an asterisk versus written labels, or different label placement, separately.

1. 1Do not change labels and validation rules in the same test.
2. 2Do not mark a backend-required field as optional.
3. 3Keep the labels visually consistent with the rest of the form.
4. 4Do not use labels so long that they cut off field text on mobile.
5. 5Keep field order and count unchanged during the test.