Forms and validation · Lesson 4 of 10 · 10 minutes

Forms and validation: Required fields

required participates in native constraint validation; identify the requirement in visible copy too.

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Your objectives

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1
Build required fields
Build this first target: <label> (for="name") containing “Name (required)”; <input> (id="name"). Inspect the structure before checking the lesson.
Hint & worked example
required participates in native constraint validation; identify the requirement in visible copy too.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<label for="name">Name (required)</label><input id="name">
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.
2
Extend the required fields example
Extend your file to include: <label> (for="name") containing “Name (required)”; <input> (id="name", required). Inspect the structure before checking the lesson.
Hint & worked example
required participates in native constraint validation; identify the requirement in visible copy too.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<label for="name">Name (required)</label><input id="name" required>
```
Common mistake to avoid: Replacing semantic elements with generic divs automatically improves accessibility.
3
Verify the complete required fields pattern
Finish the pattern with: <label> (for="name") containing “Name (required)”; <input> (id="name", name="name", required, autocomplete="name"). Inspect the structure before checking the lesson.
Hint & worked example
required participates in native constraint validation; identify the requirement in visible copy too.
The requested elements, attributes, content, and hierarchy exist outside comments.
```
<label for="name">Name (required)</label><input id="name" name="name" required autocomplete="name">
```
Common mistake to avoid: A visual appearance alone guarantees the intended HTML meaning.

Understand the pattern

required participates in native constraint validation; identify the requirement in visible copy too.

Misconceptions to reject

A visual appearance alone guarantees the intended HTML meaning.
Replacing semantic elements with generic divs automatically improves accessibility.

The preview is a sanitized subset, not a full browser compatibility test.

Worked example and expected result

<label for="name">Name (required)</label><input id="name" name="name" required autocomplete="name">

required participates in native constraint validation; identify the requirement in visible copy too.

Try a variation

Adapt the final example to a different project name while retaining its structure and relationships. A different context still needs a real browser and accessibility check.

Explain it

Which statement correctly explains required fields?Replacing semantic elements with generic divs automatically improves accessibility.required participates in native constraint validation; identify the requirement in visible copy too.A visual appearance alone guarantees the intended HTML meaning.

Apply it elsewhere

You reuse required fields in a different project. What must still be verified?The meaning, relationships, and accessible names in the new document.Nothing; passing a single exercise guarantees every future use.Only whether the source code has the same number of lines.

Keep the momentum.

Complete the lab, then explain and apply the pattern.

Next: Forms and validation: Help text relationships Try an incident drill

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MDN: HTML structure