# Checkbox

Flat, square, accent-filled checkmark.

Preview: https://design.freecodecamp.org/playground#checkbox

## Add to your project

Use React and TypeScript. Required packages: `react@>=18 <20`. No freeCodeCamp package is needed.

Copy the files below to the indicated paths, relative to your project root. If you change the layout, update relative imports too.

Import the CSS once from your application entry. For an entry in src/:

```ts
import './ui/theme/tokens.css';
import './ui/theme/base.css';
import './ui/checkbox/checkbox.css';
```

The theme is shared: reuse it if already installed. Fonts use /fonts/ URLs on your host. Download the font files listed in https://design.freecodecamp.org/registry/starter.md or change those URLs in your copied tokens.css.

## Example

```tsx
import { Checkbox } from './ui/checkbox/Checkbox';

export function Example() {
  return (
    <div style={{ display: 'grid', gap: 16, width: '100%' }}>
      <Checkbox defaultChecked label='I accept the honor code' />
      <Checkbox label='Email me certificate alerts' />
    </div>
  );
}
```

## Interaction guidance

Review https://www.w3.org/WAI/ARIA/apg/patterns/checkbox/ and test keyboard operation in your project.

## Component source

### src/ui/checkbox/Checkbox.tsx

Source: https://design.freecodecamp.org/registry/checkbox/Checkbox.tsx

```tsx
import React, { forwardRef } from 'react';

export interface CheckboxProps extends Omit<
  React.InputHTMLAttributes<HTMLInputElement>,
  'type'
> {
  label?: React.ReactNode;
  labelClassName?: string;
}

export const Checkbox = forwardRef<HTMLInputElement, CheckboxProps>(
  ({ label, labelClassName = '', className = '', id, ...rest }, ref) => {
    if (label === undefined) {
      return (
        <input
          ref={ref}
          type='checkbox'
          id={id}
          className={className}
          {...rest}
        />
      );
    }
    const classes = ['check', labelClassName].filter(Boolean).join(' ');
    return (
      <label className={classes} htmlFor={id}>
        <input
          ref={ref}
          type='checkbox'
          id={id}
          className={className}
          {...rest}
        />
        <span>{label}</span>
      </label>
    );
  }
);
Checkbox.displayName = 'Checkbox';
```

### src/ui/checkbox/checkbox.css

Source: https://design.freecodecamp.org/registry/checkbox/checkbox.css

```css
.check {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-family: var(--font-sans);
  font-size: var(--fs-md);
  color: var(--foreground-primary);
  cursor: pointer;
}
.check input[type='checkbox'] {
  width: 18px;
  height: 18px;
  margin-top: 3px;
  accent-color: var(--cta-background);
  cursor: inherit;
}
.check:has(input:disabled) {
  opacity: 0.5;
  cursor: not-allowed;
}
```

## Shared source: Theme

### src/ui/theme/tokens.css

Source: https://design.freecodecamp.org/registry/theme/tokens.css

```css
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-Light.woff') format('woff');
  font-weight: 300;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-Regular.woff') format('woff');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-Italic.woff') format('woff');
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-Bold.woff') format('woff');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-BoldItalic.woff') format('woff');
  font-weight: 700;
  font-style: italic;
  font-display: swap;
}
@font-face {
  font-family: 'Lato';
  src: url('/fonts/Lato-Black.woff') format('woff');
  font-weight: 900;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Hack-ZeroSlash';
  src: url('/fonts/Hack-ZeroSlash-Regular.woff2') format('woff2');
  font-weight: 400;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Hack-ZeroSlash';
  src: url('/fonts/Hack-ZeroSlash-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Hack-ZeroSlash';
  src: url('/fonts/Hack-ZeroSlash-Italic.woff2') format('woff2');
  font-weight: 400;
  font-style: italic;
  font-display: swap;
}
@font-face {
  font-family: 'Hack-ZeroSlash';
  src: url('/fonts/Hack-ZeroSlash-BoldItalic.woff2') format('woff2');
  font-weight: 700;
  font-style: italic;
  font-display: swap;
}

:root {
  --gray-00: #ffffff;
  --gray-00-translucent: rgba(255, 255, 255, 0.85);
  --gray-05: #f5f6f7;
  --gray-10: #dfdfe2;
  --gray-15: #d0d0d5;
  --gray-45: #858591;
  --gray-75: #3b3b4f;
  --gray-80: #2a2a40;
  --gray-85: #1b1b32;
  --gray-90: #0a0a23;
  --gray-90-translucent: rgba(10, 10, 35, 0.85);

  --purple-light: #dbb8ff;
  --purple-mid: #9400d3;
  --purple-dark: #5a01a7;
  --yellow-light: #ffc300;
  --yellow-gold: #ffbf00;
  --yellow-style: #f1be32;
  --yellow-dark: #4d3800;
  --blue-light: #99c9ff;
  --blue-light-translucent: rgba(153, 201, 255, 0.3);
  --blue-mid: #198eee;
  --blue-dark: #002ead;
  --blue-dark-translucent: rgba(0, 46, 173, 0.3);
  --green-light: #acd157;
  --green-dark: #00471b;
  --red-light: #ffadad;
  --red-dark: #850000;
  --love-light: #f8577c;
  --love-dark: #f82153;
  --orange: #eda971;

  --editor-background-light: #fffffe;
  --editor-background-dark: #2a2b40;

  --syntax-keyword: #dbb8ff;
  --syntax-fn: #99c9ff;
  --syntax-string: #acd157;
  --syntax-class: #f1be32;
  --syntax-number: #f78c6c;
  --syntax-tag: #f07178;
  --syntax-operator: #89ddff;
  --syntax-invalid: #ff5370;
  --syntax-comment: #858591;
  --syntax-plain: #eeffff;

  --font-sans:
    'Lato', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'Hack-ZeroSlash', 'Fira Mono', Menlo, Consolas, monospace;

  --fs-base: 18px;
  --fs-sm: 16px;
  --fs-md: 18px;
  --fs-lg: 24px;
  --fs-xl: 32px;
  --fs-2xl: 42px;
  --fs-3xl: 56px;
  --fs-display: clamp(2.5rem, 5vw, 3.75rem);

  --lh-tight: 1.2;
  --lh-snug: 1.33;
  --lh-base: 1.42857143;
  --lh-loose: 1.6;

  --fw-light: 300;
  --fw-regular: 400;
  --fw-bold: 700;
  --fw-black: 900;

  --space-0: 0;
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;

  --border-width-hair: 1px;
  --border-width-default: 2px;
  --border-width-thick: 3px;
  --radius-none: 0;
  --radius-sm: 2px;

  --focus-outline-color: var(--blue-mid);
  --focus-outline-width: 3px;

  --z-breadcrumbs: 100;
  --z-flash: 150;
  --z-site-header: 200;
  --z-modal: 1050;

  --ease-snap: cubic-bezier(0.2, 0.8, 0.2, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 120ms;
  --dur-base: 180ms;
  --dur-slow: 260ms;

  --header-height: 48px;
  --breadcrumbs-height: 32px;
  --sidebar-width: 288px;
  --content-max: 1040px;

  color-scheme: dark;
}

.dark-palette,
:root {
  color-scheme: dark;
  --foreground-primary: var(--gray-00);
  --foreground-secondary: var(--gray-05);
  --foreground-tertiary: var(--gray-10);
  --foreground-quaternary: var(--gray-15);
  --foreground-muted: #b0b0bd;

  --background-primary: var(--gray-90);
  --background-primary-translucent: var(--gray-90-translucent);
  --background-secondary: var(--gray-85);
  --background-tertiary: #33334f;
  --background-quaternary: #4b4b66;

  --highlight-color: var(--blue-light);
  --highlight-background: var(--blue-dark);
  --selection-color: var(--blue-light-translucent);

  --success-color: var(--green-light);
  --success-background: var(--green-dark);
  --danger-color: var(--red-light);
  --danger-background: var(--red-dark);
  --warning-color: var(--yellow-light);
  --warning-background: var(--yellow-dark);
  --purple-color: var(--purple-light);
  --purple-background: var(--purple-dark);
  --love-color: var(--love-light);

  --editor-background: var(--editor-background-dark);

  --cta-background: var(--yellow-gold);
  --cta-foreground: var(--gray-90);

  --surface-elevation-1: rgba(255, 255, 255, 0.045);
  --surface-elevation-2: rgba(255, 255, 255, 0.09);
  --border-soft: var(--background-tertiary);
  --border-strong: var(--background-quaternary);
}

.light-palette {
  --foreground-primary: var(--gray-90);
  --foreground-secondary: var(--gray-85);
  --foreground-tertiary: var(--gray-80);
  --foreground-quaternary: var(--gray-75);
  --foreground-muted: #5a5a68;

  --background-primary: var(--gray-00);
  --background-primary-translucent: var(--gray-00-translucent);
  --background-secondary: var(--gray-05);
  --background-tertiary: #c5c5cc;
  --background-quaternary: #a8a8b4;

  --highlight-color: var(--blue-dark);
  --highlight-background: var(--blue-light);
  --selection-color: var(--blue-dark-translucent);

  --success-color: var(--green-dark);
  --success-background: var(--green-light);
  --danger-color: var(--red-dark);
  --danger-background: var(--red-light);
  --warning-color: var(--yellow-dark);
  --warning-background: var(--yellow-light);
  --purple-color: var(--purple-dark);
  --purple-background: var(--purple-light);
  --love-color: var(--love-dark);

  --editor-background: var(--editor-background-light);

  --cta-background: var(--yellow-gold);
  --cta-foreground: var(--gray-90);

  --surface-elevation-1: rgba(10, 10, 35, 0.05);
  --surface-elevation-2: rgba(10, 10, 35, 0.09);
  --border-soft: var(--background-tertiary);
  --border-strong: var(--background-quaternary);

  color-scheme: light;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: var(--fs-md);
  font-family: var(--font-sans);
  line-height: var(--lh-base);
  color: var(--foreground-primary);
  background: var(--background-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 24px);
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--foreground-primary);
  background: var(--background-primary);
}

::selection {
  background: var(--selection-color);
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-sans);
  font-weight: var(--fw-bold);
  color: var(--foreground-primary);
  line-height: var(--lh-snug);
  margin: 0 0 12px 0;
}
h1 {
  font-size: var(--fs-3xl);
  line-height: var(--lh-tight);
  letter-spacing: -0.01em;
}
h2 {
  font-size: var(--fs-2xl);
  letter-spacing: -0.005em;
}
h3 {
  font-size: var(--fs-xl);
}
h4 {
  font-size: var(--fs-lg);
}
h5 {
  font-size: var(--fs-md);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
h6 {
  font-size: var(--fs-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--foreground-muted);
  font-family: var(--font-mono);
}

p {
  margin: 0 0 12px 0;
}

a {
  color: var(--highlight-color);
  text-decoration: underline;
  text-underline-position: under;
  text-underline-offset: 0.1em;
}
a:hover {
  color: var(--foreground-primary);
}

code,
pre,
kbd,
samp {
  font-family: var(--font-mono);
  font-size: 16px;
}
code {
  background: var(--background-tertiary);
  color: var(--foreground-tertiary);
}
:not(pre) > code {
  border: 1px solid var(--background-quaternary);
  padding: 1px 4px;
  overflow-wrap: anywhere;
  word-break: break-word;
}
pre {
  background: var(--editor-background);
  color: var(--foreground-tertiary);
  padding: 14px 16px;
  font-size: 14px;
  line-height: var(--lh-base);
  max-width: 100%;
  overflow-x: auto;
  margin: 0;
}
pre code {
  display: block;
  width: max-content;
  min-width: 100%;
  background: transparent;
  border: 0;
  padding: 0;
}

:focus-visible {
  outline: var(--focus-outline-width) solid var(--focus-outline-color);
  outline-offset: 0;
}

hr {
  border: 0;
  border-top: 1px solid var(--background-quaternary);
  margin: 24px 0;
}

::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}
::-webkit-scrollbar-track {
  background: var(--background-primary);
}
::-webkit-scrollbar-thumb {
  background: var(--background-quaternary);
  border: 2px solid var(--background-primary);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--foreground-muted);
}
```

### src/ui/theme/base.css

Source: https://design.freecodecamp.org/registry/theme/base.css

```css
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
```

## Adapting this component

Keep the component's semantics and keyboard behavior. Use the CSS variables to change its appearance. Check the result in your project; copied source does not receive automatic updates.

Source revision: 1914914 (2026-09-08). Component source: BSD-3-Clause. Preserve the license notice: https://design.freecodecamp.org/license.txt.

Design rules: https://design.freecodecamp.org/handbook.md