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---
name: frontend-a11y
description: >
Accessibility patterns for React and Next.js — semantic HTML, ARIA attributes,
form labeling, keyboard navigation, focus management, and screen reader support.
Use when building any interactive UI component or form.
origin: community
---
Practical accessibility patterns for React and Next.js. Covers the issues most commonly flagged in code review: missing form labels, incorrect ARIA usage, non-semantic interactive elements, and broken keyboard navigation.
- Building or reviewing form components (`<input>`, `<select>`, `<textarea>`)
- Creating interactive elements (modals, dropdowns, tooltips, tabs)
- Using `<div>` or `<span>` with `onClick`
- Adding `aria-*` attributes to any element
- Implementing keyboard navigation or focus management
- Receiving accessibility feedback from code review tools (CodeRabbit, ESLint a11y)
- Building components that must support screen readers
## Form Accessibility
Missing `htmlFor` / `id` pairing and disconnected error messages are the most common issues flagged in code review.
### Label Connection
```tsx
// BAD: label has no connection to input — screen readers cannot associate them
<label>Email</label>
<input type="email" />
// GOOD: htmlFor matches input id
<label htmlFor="email">Email</label>
<input id="email" type="email" />
```
```tsx
// BAD: visual-only asterisk conveys nothing to screen readers
<label htmlFor="email">Email *</label>
<input id="email" type="email" />
// GOOD: required enables native browser validation; aria-required signals it to screen readers
<label htmlFor="email">
Email <span aria-hidden="true">*</span>
</label>
<input id="email" type="email" required aria-required="true" />
```
```tsx
// BAD: error text exists visually but is not linked to the input
<input id="email" type="email" />
<span className="error">Invalid email address</span>
// GOOD: aria-describedby connects input to its error message
// aria-invalid signals the invalid state to screen readers
<input
id="email"
type="email"
aria-describedby="email-error"
aria-invalid={!!error}
/>
{error && (
<span id="email-error" role="alert">
{error}
</span>
)}
```
```tsx
interface LoginFormProps {
onSubmit: (email: string, password: string) => void;
}
export function LoginForm({ onSubmit }: LoginFormProps) {
const [email, setEmail] = useState('');
const [password, setPassword] = useState('');
const [errors, setErrors] = useState<{ email?: string; password?: string }>({});
const handleSubmit = (e: React.FormEvent) => {
e.preventDefault();
const newErrors: typeof errors = {};
if (!email) newErrors.email = 'Email is required';
if (!password) newErrors.password = 'Password is required';
if (Object.keys(newErrors).length) {
setErrors(newErrors);
return;
}
onSubmit(email, password);
};
return (
<form onSubmit={handleSubmit} noValidate>
<div>
<label htmlFor="email">
Email <span aria-hidden="true">*</span>
</label>
<input
id="email"
type="email"
value={email}
onChange={e => setEmail(e.target.value)}
aria-required="true"
aria-describedby={errors.email ? 'email-error' : undefined}
aria-invalid={!!errors.email}
autoComplete="email"
/>
{errors.email && (
<span id="email-error" role="alert">
{errors.email}
</span>
)}
</div>
<div>
<label htmlFor="password">
Password <span aria-hidden="true">*</span>
</label>
<input
id="password"
type="password"
value={password}
onChange={e => setPassword(e.target.value)}
aria-required="true"
aria-describedby={errors.password ? 'password-error' : undefined}
aria-invalid={!!errors.password}
autoComplete="current-password"
/>
{errors.password && (
<span id="password-error" role="alert">
{errors.password}
</span>
)}
</div>
<button type="submit">Log in</button>
</form>
);
}
```
Use the element that matches the intent. Screen readers and keyboard users depend on native semantics.
```tsx
// BAD: div has no role, no keyboard support, no accessible name
<div onClick={handleClick}>Submit</div>
// GOOD: button is focusable, activates on Enter/Space, announces as "button"
<button type="button" onClick={handleClick}>Submit</button>
```
```tsx
// BAD: non-semantic navigation
<div onClick={() => navigate('/home')}>Home</div>
// GOOD: anchor supports right-click, middle-click, and keyboard navigation
<a href="/home">Home</a>
```
```tsx
// BAD: heading hierarchy skipped (h1 to h4)
<h1>Dashboard</h1>
<h4>Recent Activity</h4>
// GOOD: sequential heading levels
<h1>Dashboard</h1>
<h2>Recent Activity</h2>
```
Use ARIA only when native HTML semantics are insufficient. Wrong ARIA is worse than no ARIA.
```tsx
// aria-label: inline string label — use when no visible label text exists
<button aria-label="Close modal">
<XIcon />
</button>
// aria-labelledby: references another element's text — use when a visible label exists
<section aria-labelledby="section-title">
<h2 id="section-title">Recent Orders</h2>
{/* content */}
</section>
```
```tsx
// Provides supplementary description beyond the label
<button
aria-describedby="delete-warning"
onClick={handleDelete}
> Delete account
</button>
<p id="delete-warning">This action cannot be undone.</p>
```
```tsx
// Use aria-live to announce content that updates without a page reload
// polite: waits for user to finish current action before announcing
// assertive: interrupts immediately — use only for urgent errors
export function StatusMessage({ message, isError }: { message: string; isError?: boolean }) {
return (
<div role="status" aria-live={isError ? 'assertive' : 'polite'} aria-atomic="true">
{message}
</div>
);
}
```
```tsx
export function Accordion({ title, children }: { title: string; children: React.ReactNode }) {
const [isOpen, setIsOpen] = useState(false);
const contentId = useId();
return (
<div>
<button aria-expanded={isOpen} aria-controls={contentId} onClick={() => setIsOpen(prev => !prev)}>
{title}
</button>
<div id={contentId} hidden={!isOpen}>
{children}
</div>
</div>
);
}
```
Every interactive element must be reachable and operable by keyboard alone.
```tsx
export function Dropdown({ options, onSelect }: { options: string[]; onSelect: (value: string) => void }) {
const [isOpen, setIsOpen] = useState(false);
const [activeIndex, setActiveIndex] = useState(0);
const listId = useId();
if (!options.length) return null;
const handleKeyDown = (e: React.KeyboardEvent) => {
switch (e.key) {
case 'ArrowDown':
e.preventDefault();
setActiveIndex(i => Math.min(i + 1, options.length - 1));
break;
case 'ArrowUp':
e.preventDefault();
setActiveIndex(i => Math.max(i - 1, 0));
break;
case 'Enter':
case ' ':
e.preventDefault();
if (isOpen) onSelect(options[activeIndex]);
setIsOpen(prev => !prev);
break;
case 'Escape':
setIsOpen(false);
break;
}
};
return (
<div
role="combobox"
aria-expanded={isOpen}
aria-haspopup="listbox"
aria-controls={listId}
tabIndex={0}
onKeyDown={handleKeyDown}
onClick={() => setIsOpen(prev => !prev)}
>
<span>{options[activeIndex]}</span>
{isOpen && (
<ul id={listId} role="listbox">
{options.map((option, index) => (
<li
key={option}
role="option"
aria-selected={index === activeIndex}
onClick={() => {
onSelect(option);
setIsOpen(false);
}}
>
{option}
</li>
))}
</ul>
)}
</div>
);
}
```
Focus must move logically when UI state changes — especially for modals and route transitions.
> This example covers initial focus and restoration. For a full focus trap (Tab/Shift+Tab cycling within the modal), use a library like [`focus-trap-react`](https://github.com/focus-trap/focus-trap-react) which handles edge cases like dynamic content and nested portals.
```tsx
export function Modal({ isOpen, onClose, title, children }: { isOpen: boolean; onClose: () => void; title: string; children: React.ReactNode }) {
const modalRef = useRef<HTMLDivElement>(null);
const previousFocusRef = useRef<HTMLElement | null>(null);
useEffect(() => {
if (isOpen) {
// Save currently focused element and move focus into modal
previousFocusRef.current = document.activeElement as HTMLElement;
modalRef.current?.focus();
} else {
// Restore focus to the element that opened the modal
previousFocusRef.current?.focus();
}
}, [isOpen]);
if (!isOpen) return null;
return (
<div ref={modalRef} role="dialog" aria-modal="true" aria-labelledby="modal-title" tabIndex={-1} onKeyDown={e => e.key === 'Escape' && onClose()}>
<h2 id="modal-title">{title}</h2>
{children}
<button onClick={onClose}>Close</button>
</div>
);
}
```
```tsx
// BAD: decorative icon announced as unlabeled image
<img src="/icon.svg" />
// GOOD: decorative image hidden from screen readers
<img src="/decoration.png" alt="" aria-hidden="true" />
// GOOD: meaningful image with descriptive alt text
<img src="/chart.png" alt="Monthly revenue increased 23% from January to March" />
// GOOD: icon button with accessible label
<button aria-label="Delete item">
<TrashIcon aria-hidden="true" />
</button>
```
Respect users who have requested reduced motion in their OS settings.
```tsx
export function useReducedMotion(): boolean {
const [prefersReduced, setPrefersReduced] = useState(false);
useEffect(() => {
const mq = window.matchMedia('(prefers-reduced-motion: reduce)');
setPrefersReduced(mq.matches);
const handler = (e: MediaQueryListEvent) => setPrefersReduced(e.matches);
mq.addEventListener('change', handler);
return () => mq.removeEventListener('change', handler);
}, []);
return prefersReduced;
}
// Usage
export function AnimatedCard({ children }: { children: React.ReactNode }) {
const reduceMotion = useReducedMotion();
return (
<div
style={{
transition: reduceMotion ? 'none' : 'transform 300ms ease'
}}
>
{children}
</div>
);
}
```
```tsx
// BAD: onClick on non-interactive element with no keyboard support
<div onClick={handleClick}>Click me</div>
// BAD: aria-label on a div that has no role
<div aria-label="Navigation">...</div>
// BAD: placeholder used as a substitute for label
<input placeholder="Enter your email" />
// BAD: positive tabIndex creates unpredictable tab order
<button tabIndex={3}>Submit</button>
// BAD: aria-hidden on a focusable element — keyboard users get trapped
<button aria-hidden="true">Open</button>
// BAD: role="button" on div without keyboard handler
<div role="button" onClick={handleClick}>Submit</div>
// Missing: tabIndex={0}, onKeyDown for Enter/Space
```
Before submitting any interactive component for review:
- [ ] Every `<input>`, `<select>`, and `<textarea>` has a connected `<label>` via `htmlFor`/`id`
- [ ] Error messages are linked with `aria-describedby` and marked `role="alert"`
- [ ] No `onClick` on `<div>` or `<span>` without `role`, `tabIndex`, and `onKeyDown`
- [ ] Icon-only buttons have `aria-label`
- [ ] Decorative images use `alt=""` and `aria-hidden="true"`
- [ ] Modals restore focus on close (for full focus trapping with Tab/Shift+Tab cycling, use a library like `focus-trap-react`)
- [ ] Dynamic content updates use `aria-live`
- [ ] `prefers-reduced-motion` is respected for animations
## Related Skills
- `frontend-patterns` — general React component and state patterns
- `design-system` — design token and component consistency
- `motion-ui` — animation patterns with accessibility considerations