Radio buttons and checkboxes in HTML - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main difference between radio buttons and checkboxes in HTML?

Radio buttons allow the user to select only one option from a group, while checkboxes let the user select multiple options independently.

beginner

How do you group radio buttons so only one can be selected at a time?

Give all radio buttons in the group the same name attribute value. This links them so only one can be selected.

beginner

What attribute do you use to make a checkbox or radio button selected by default?

Use the checked attribute on the <input> element to make it selected when the page loads.

beginner

Why should you use <label> elements with radio buttons and checkboxes?

Labels improve accessibility by making it easier to click the input and help screen readers understand the form controls.

intermediate

How can you make a group of checkboxes or radio buttons accessible for keyboard users?

Use <label> tags linked with inputs, ensure logical tab order, and use <fieldset> with <legend> to group related controls.

Which attribute groups radio buttons so only one can be selected?

A name

B id

C value

D checked

Radio buttons with the same 'name' attribute belong to the same group, allowing only one selection.

What happens if you give checkboxes the same name attribute?

A Checkboxes behave like radio buttons

B Only one checkbox can be selected

C Checkboxes become disabled

D Multiple checkboxes can be selected independently

Checkboxes with the same name can still be selected independently; the name attribute does not limit selection for checkboxes.

Which HTML element improves accessibility by linking text to a checkbox or radio button?

A <div>

B <span>

C <label>

D <section>

The element associates descriptive text with form controls, improving accessibility and usability.

How do you make a radio button selected by default?

A Add the attribute active

B Add the attribute checked

C Add the attribute default

D Add the attribute selected

The 'checked' attribute marks a radio button or checkbox as selected when the page loads.

Which input type allows multiple selections?

A checkbox

B radio

C text

D button

Checkboxes allow users to select multiple options independently.

Explain how to create a group of radio buttons where only one option can be selected. Include how to make one option selected by default.

Think about how browsers know which radio buttons belong together.

Describe the accessibility best practices when using checkboxes and radio buttons in a form.

Consider how people using keyboards or screen readers interact with forms.

Practice

1. Which input type allows a user to select only one option from a group?
<input type="?">

easy

A. button

B. checkbox

C. radio

D. text

Solution

1. Step 1: Understand input types

   The radio input type is designed for selecting one option from many.

2. Step 2: Compare with other types

   checkbox allows multiple selections, text is for typing, and button triggers actions.

3. Final Answer:

   radio -> Option C

4. Quick Check:

   Single choice = radio [OK]

Hint: Radio = one choice, Checkbox = many choices [OK]

Common Mistakes:

• Confusing checkbox with radio
• Thinking text input allows selection
• Using button for selection

2. Which of the following is the correct syntax to create a checkbox with label "Subscribe"?

easy

A. Subscribe

B. Subscribe

C. Subscribe

D. Subscribe

Solution

1. Step 1: Check input and label usage

   The correct checkbox uses <input type="checkbox"> and a <label> with matching for attribute.

2. Step 2: Identify invalid syntax

   The other options use invalid syntax: A uses a non-existent <checkbox> tag, B incorrectly closes the input with text inside, and D uses an invalid checkbox attribute.

3. Final Answer:

   <input type="checkbox" id="sub"><label for="sub">Subscribe</label> -> Option B

4. Quick Check:

   Checkbox + label with for = correct syntax [OK]

Hint: Use with [OK]

Common Mistakes:

• Using non-existent <checkbox> tag
• Missing type attribute
• Not linking label with for attribute

3. What will be the result when this HTML is rendered?

<form>
  <input type="radio" name="color" id="red" value="Red"><label for="red">Red</label>
  <input type="radio" name="color" id="blue" value="Blue" checked><label for="blue">Blue</label>
  <input type="radio" name="color" id="green" value="Green"><label for="green">Green</label>
</form>

medium

A. Only the Blue radio button is selected by default

B. All three radio buttons are selected

C. No radio buttons are selected by default

D. The Green radio button is selected by default

Solution

1. Step 1: Identify checked attribute

   The Blue radio button has the checked attribute, so it is selected by default.

2. Step 2: Understand radio group behavior

   Only one radio button in a group (same name) can be selected at a time.

3. Final Answer:

   Only the Blue radio button is selected by default -> Option A

4. Quick Check:

   Checked attribute sets default selection [OK]

Hint: Look for checked attribute to find default selected radio [OK]

Common Mistakes:

• Assuming multiple radios can be selected
• Ignoring the checked attribute
• Confusing radio with checkbox behavior

4. This code snippet is intended to create two checkboxes with labels, but only one label works correctly. What is the error?

<input type="checkbox" id="news"><label for="news">News</label>
<input type="checkbox" id="updates"><label>Updates</label>

medium

A. The second label is missing the for attribute linking it to the checkbox

B. The first checkbox is missing a name attribute

C. Checkboxes cannot have labels

D. The id attribute should be on the label, not the input

Solution

1. Step 1: Check label associations

   The first label uses for="news" linking it to the checkbox with id "news".

2. Step 2: Identify missing for attribute

   The second label lacks a for attribute, so it is not linked to the checkbox with id "updates".

3. Final Answer:

   The second label is missing the for attribute linking it to the checkbox -> Option A

4. Quick Check:

   Label needs for attribute to link input [OK]

Hint: Labels must have for attribute matching input id [OK]

Common Mistakes:

• Assuming name attribute is required for labels
• Thinking labels can't be used with checkboxes
• Placing id on label instead of input

5. You want to create a form where users can select their favorite fruits. They can pick any number of fruits, but only one fruit size (Small, Medium, Large). Which input types should you use for fruits and sizes respectively?

hard

A. Radio buttons for both fruits and sizes

B. Radio buttons for fruits, Checkboxes for sizes

C. Checkboxes for both fruits and sizes

D. Checkboxes for fruits, Radio buttons for sizes

Solution

1. Step 1: Understand selection rules

   Users can pick multiple fruits, so checkboxes are suitable for fruits.

2. Step 2: Single choice for size

   Only one size can be selected, so radio buttons are suitable for sizes.

3. Final Answer:

   Checkboxes for fruits, Radio buttons for sizes -> Option D

4. Quick Check:

   Multiple choice = checkbox, single choice = radio [OK]

Hint: Multiple selections use checkbox; single selection uses radio [OK]

Common Mistakes:

• Using radio buttons for multiple selections
• Using checkboxes for single selection
• Not grouping radio buttons by name