In a regular HTML form, a label that's visually connected to an input field is usually also technically connected, and a screen reader "understands" on its own which label belongs to which field. In a PDF file this doesn't happen automatically: a label and a field can look adjacent on screen but technically be two completely separate objects, with no connection between them. This article explains how to close that gap.

In short โ€” what this guide covers

  1. The tooltip is the field's accessible name
  2. Text fields, checkboxes, and radio buttons
  3. A logical tab order
  4. How to mark a required field

The Tooltip Is the Field's Accessible Name

Unlike HTML, in PDF forms the Tooltip field of every field is what actually serves as the accessible name a screen reader reads aloud. The basic rule: the tooltip's content must be identical, or equivalent, to the visible label next to the field. If the visible label says "Full Name," the tooltip must say something equivalent in meaning โ€” not a generic label like "Text Field 1."

You set a tooltip in Acrobat via Prepare Form โ–ธ right-click the field โ–ธ Properties โ–ธ General tab โ–ธ Tooltip field.

Text Fields, Checkboxes, and Radio Buttons

Every field type has its own considerations: for text fields, the tooltip is usually identical to the label beside it. For checkboxes and radio buttons, it's important that the tooltip describes the specific option being selected, not just the group's name โ€” for example, "I agree to receive email updates," not just "Agree." For a group of radio buttons (for example, a "Yes/No" choice), it's also worth making sure all the buttons in the group are tagged together, so a screen reader understands they're mutually exclusive options.

Illustrative diagram An accessible form field with tooltip and tab order Example of form fields with tab-order numbering and tooltip content matching the label Form Field with Label, Tooltip, and Tab Order 1 Full Name (required) 2 Email Address 3 I agree to receive updates Tooltip = "Full Name (required)" Matches the visible label Unlike HTML forms, in PDF files the tooltip is the actual accessible name โ€” it must match the visible label
Three fields with tab-order numbering (1, 2, 3) matching the visual reading order, and tooltip content identical to the visible label.

A Logical Tab Order

When filling out a form using the keyboard alone (no mouse), the Tab key moves between fields according to the tab order defined in the file โ€” not necessarily the visual position on the page. If the tab order doesn't match the logical reading order, the user "jumps" between fields in a confusing way. In Acrobat, under the Prepare Form menu, you can turn on "Show Tab Numbers" to clearly see the current order, and correct it as needed via the tag structure.

๐Ÿ’ก Practical Tip

It's better to fix an incorrect tab order through the tag structure (the order of objects in the tree) rather than manually field-by-field โ€” because a manual change breaks easily the next time the form is updated.

How to Mark a Required Field

A required field needs to indicate this both visually (an asterisk, for example) and in the tooltip itself โ€” for example, "Full Name (required)." This way, a user relying on text-to-speech understands immediately that the field is required, without having to wait for a submission error that reveals it only after the fact.

Do You Have Downloadable PDF Forms on Your Site?

Our tool checks the accessibility of form fields โ€” tooltips, tab order, and tagging โ€” as part of the full scan.

Scan your site for free โ†