Shadcn Guide

shadcn/ui Guide

Purpose

shadcn/ui is not a component library — it's a system to build your own component library. Components are copied into your project as open source code you fully own and control. Two primitive variants are available: Base UI (by MUI) and Radix UI (default).

Core Principles: Open Code, Composition, Distribution (schema + CLI), Beautiful Defaults, AI-Ready.

Upstream updates: shadcn/ui follows a headless component architecture. The core receives fixes by updating dependencies (e.g. radix-ui, input-otp). The topmost layer (closest to your design system) stays open for modification and is not coupled with the library implementation.

Do NOT use this guide for Chakra UI, Material UI (MUI), Ant Design, or vanilla Tailwind CSS without shadcn/ui context — those have different installation, theming, and component APIs.

Quick Start

# Initialize a new project (or add to existing)
npx shadcn@latest init

# Add components
npx shadcn@latest add button dialog card

# Add all components
npx shadcn@latest add --all

# Interactive setup with custom themes
npx shadcn@latest create

CLI Commands

Key CLI flags: -y (skip prompts), -o (overwrite), -a (all), -c <cwd> (working directory), -s (silent). See references/configuration.md for full CLI command details.

Configuration (components.json)

Located at project root. Created by init. Schema: https://ui.shadcn.com/schema.json

{
  "$schema": "https://ui.shadcn.com/schema.json",
  "style": "new-york",
  "rsc": true,
  "tsx": true,
  "tailwind": {
    "config": "",
    "css": "app/globals.css",
    "baseColor": "neutral",
    "cssVariables": true
  },
  "iconLibrary": "lucide",
  "aliases": {
    "components": "@/components",
    "utils": "@/lib/utils",
    "ui": "@/components/ui",
    "lib": "@/lib",
    "hooks": "@/hooks"
  }
}

Immutable after init: style, baseColor, cssVariables. Use new-york style (default is deprecated).

Theming (CSS Variables)

Colors use OKLCH format. Convention: --[role] for background, --[role]-foreground for text.

:root {
  --background: oklch(1 0 0);
  --foreground: oklch(0.145 0 0);
  --primary: oklch(0.205 0 0);
  --primary-foreground: oklch(0.985 0 0);
  --secondary: oklch(0.97 0 0);
  --muted: oklch(0.97 0 0);
  --muted-foreground: oklch(0.556 0 0);
  --accent: oklch(0.97 0 0);
  --destructive: oklch(0.577 0.245 27.325);
  --border: oklch(0.922 0 0);
  --input: oklch(0.922 0 0);
  --ring: oklch(0.708 0 0);
  --radius: 0.625rem;
}

Usage: <div className="bg-primary text-primary-foreground" />

Adding custom colors:

:root { --warning: oklch(0.84 0.16 84); --warning-foreground: oklch(0.28 0.07 46); }
.dark { --warning: oklch(0.41 0.11 46); --warning-foreground: oklch(0.99 0.02 95); }
@theme inline { --color-warning: var(--warning); --color-warning-foreground: var(--warning-foreground); }

Base colors: neutral, stone, zinc, gray, slate.

Component Pattern

All components follow the same pattern:

npx shadcn@latest add [component-name]

import { Component } from "@/components/ui/component"

export function Example() {
  return <Component>Content</Component>
}

58 components available in both Base UI and Radix variants. See references/components-*.md (6 files by category).

Most-used components: Button, Card, Dialog, Input, Select, Table, Tabs, Form/Field, Sidebar, Sheet, Dropdown Menu, Command, Toast (Sonner), Badge, Avatar.

Essential Utility

// lib/utils.ts — created by init
import { clsx, type ClassValue } from "clsx"
import { twMerge } from "tailwind-merge"

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs))
}

JavaScript Support (TypeScript Opt-Out)

Set "tsx": false in components.json to generate .jsx files instead of .tsx:

{ "tsx": false }

Configure import aliases in jsconfig.json:

{
  "compilerOptions": {
    "paths": { "@/*": ["./*"] }
  }
}

v0 Integration

Every shadcn/ui component is editable on v0.dev — AI-powered customization in natural language, then paste into your app. Requires a free Vercel account.

Open in v0 for registries: If your registry is publicly accessible, use the endpoint: https://v0.dev/chat/api/open?url=[REGISTRY_ITEM_URL]

Limitations: Open in v0 does NOT support cssVars, css, envVars, namespaced registries, or advanced authentication (only query parameter auth with ?token=).

Figma Resources

Community-contributed Figma kits for design-to-development workflow:

Free: Obra shadcn/ui (MIT, design-to-code plugin), shadcn/ui components by Sitsiilia Bergmann, shadcn/ui design system by Pietro Schirano.

Paid: shadcn/ui kit (shadcndesign.com), Shadcraft UI Kit (shadcraft.com, with tweakcn theming), shadcn/studio UI Kit (shadcnstudio.com/figma, 550+ blocks, 10+ templates).

Blocks (Community Contributions)

Blocks are community-contributed complex components (dashboards, marketing sections, product pages). Contribute via PR to github.com/shadcn-ui/ui.

Structure: apps/www/registry/new-york/blocks/[block-name]/ with page.tsx, components/, hooks/, lib/. Register in registry-blocks.tsx with required fields: name, description, type, files, categories. Build with pnpm registry:build, preview at localhost:3333/blocks/[CATEGORY].

See references/registry-advanced.md for full blocks contribution workflow.

Community Registries (Directory)

Community registries are built into the CLI — no configuration needed. Install with npx shadcn add @<registry>/<component>.

Security warning: Community registries are maintained by third-party developers. Always review code on installation.

Browse the directory at ui.shadcn.com/docs/registry. Add your registry to the index via PR to apps/v4/registry/directory.json.

Legacy Docs

For Tailwind v3 projects, visit v3.shadcn.com. Current docs cover Tailwind v4 only.

Key Rules & Constraints

1. Style is immutable — cannot change style, baseColor, or cssVariables after init
2. Toast is deprecated — use Sonner (npx shadcn@latest add sonner)
3. Default style deprecated — use new-york
4. Tailwind v4 — use @theme inline directive, leave tailwind.config blank, use OKLCH colors
5. React 19 — no more forwardRef, use React.ComponentProps<>, all primitives have data-slot
6. Animation library — tw-animate-css replaces tailwindcss-animate
7. Aliases must match tsconfig.json / jsconfig.json paths
8. Imports — use @/components/ui/[component] path pattern
9. npm + React 19 — may need --force or --legacy-peer-deps flag
10. Monorepo — run CLI from apps/web, components install to packages/ui
11. JavaScript — set "tsx": false in components.json, use jsconfig.json for aliases
12. Legacy — Tailwind v3 docs at v3.shadcn.com; current docs are v4 only

Installation (Framework Quick Reference)

See references/installation.md for full step-by-step guides.

Dark Mode

Use next-themes (Next.js), remix-themes (Remix), or custom context (Vite/Astro).

// Next.js: wrap in ThemeProvider
import { ThemeProvider } from "@/components/theme-provider"
<ThemeProvider attribute="class" defaultTheme="system" enableSystem disableTransitionOnChange>
  {children}
</ThemeProvider>

See references/patterns.md for full dark mode setup per framework.

Forms

Two approaches: React Hook Form (with zod) or TanStack Form. Use with Field component for accessible form fields.

<Field>
  <FieldLabel htmlFor="email">Email</FieldLabel>
  <Input id="email" type="email" />
  <FieldDescription>We'll never share your email.</FieldDescription>
  <FieldError>Invalid email address</FieldError>
</Field>

See references/forms.md for complete form integration guides.

Registry System

Distribute custom components, hooks, pages via the registry schema:

{
  "$schema": "https://ui.shadcn.com/schema/registry.json",
  "name": "acme",
  "homepage": "https://acme.com",
  "items": [{ "name": "hello-world", "type": "registry:block", "files": [...] }]
}

Build: npx shadcn@latest build → serves at /r/[name].json

Install from registries: npx shadcn@latest add @acme/button @v0/dashboard

See references/registry-core.md for full registry documentation.

Troubleshooting

• npm peer dependency errors (React 19): Use --force or --legacy-peer-deps flag. See references/configuration.md.
• Components not styled: Verify tailwind.css path in components.json points to your global CSS. Ensure @theme inline block is present.
• Path alias not resolving: Aliases in components.json must match tsconfig.json / jsconfig.json. For Vite, also update vite.config.ts resolve aliases.
• Wrong style after init: style, baseColor, cssVariables are immutable. Delete components.json and re-run npx shadcn@latest init.
• Tailwind v3 vs v4 confusion: Leave tailwind.config blank for v4. Legacy v3 docs at v3.shadcn.com.
• RSC errors in non-Next.js: Set rsc: false in components.json for Vite, Remix, Astro, Gatsby.
• Missing animations: Replace tailwindcss-animate with tw-animate-css. Add @import "tw-animate-css" to CSS.
• Monorepo component not found: Run CLI from apps/web, not project root. Both workspaces need components.json.

Reference Files

• references/components-overlay.md — Overlays: Alert Dialog, Command, Dialog, Drawer, Hover Card, Popover, Sheet, Tooltip
• references/components-navigation.md — Navigation: Breadcrumb, Context Menu, Dropdown Menu, Menubar, Navigation Menu, Pagination, Sidebar, Tabs
• references/components-form-inputs.md — Form inputs: Combobox, Field, Input, Input Group, Input OTP, Label, Native Select, Select, Textarea
• references/components-form-controls.md — Form controls: Button, Button Group, Calendar, Checkbox, Date Picker, Radio Group, Slider, Switch, Toggle, Toggle Group
• references/components-data-display.md — Data display: Alert, Avatar, Badge, Card, Carousel, Chart, Data Table, Empty, Item, Table, Typography
• references/components-layout.md — Layout & feedback: Accordion, Aspect Ratio, Collapsible, Direction, Kbd, Progress, Resizable, Scroll Area, Separator, Skeleton, Sonner, Spinner
• references/forms.md — Form patterns (React Hook Form + Zod, TanStack Form, Server Actions, Field component)
• references/patterns.md — Dark mode (per framework), RTL support, monorepo setup
• references/installation.md — Complete framework installation guides
• references/configuration.md — components.json, theming, CSS variables, Tailwind v4 migration
• references/registry-core.md — Registry system: schema, item types, files, dependencies, namespaces
• references/registry-advanced.md — Registry advanced: authentication, MCP server, blocks, Open in v0, FAQ