SKILL.md

React Email

Name: react-email
Author: resend

Build and send HTML emails using React components - a modern, component-based approach to email development that works across all major email clients.

Installation

npm i react-email

Or scaffold a new project:

npx create-email@latest

cd react-email-starter

npm install

npm run dev

This works with any package manager (npm, yarn, pnpm, bun) — substitute accordingly.

The dev server runs at localhost:3000 with a preview interface for templates in the emails folder.

Adding to an Existing Project

Install the packages and add a script to your package.json:

{

  "scripts": {

    "email": "email dev --dir emails --port 3000"

  }

}

Make sure the path to the emails folder is relative to the base project directory. Ensure tsconfig.json includes proper support for JSX.

Basic Email Template

Create an email component with proper structure using the Tailwind component for styling:

import {

  Html,

  Head,

  Preview,

  Body,

  Container,

  Heading,

  Text,

  Button,

  Tailwind,

  pixelBasedPreset

} from 'react-email';

interface WelcomeEmailProps {

  name: string;

  verificationUrl: string;

}

export default function WelcomeEmail({ name, verificationUrl }: WelcomeEmailProps) {

  return (

    <Html lang="en">

      <Tailwind

        config={{

          presets: [pixelBasedPreset],

          theme: {

            extend: {

              colors: {

                brand: '#007bff',

              },

            },

          },

        }}

      >

        <Head />

        <Body className="bg-gray-100 font-sans">

          <Preview>Welcome - Verify your email</Preview>

          <Container className="max-w-xl mx-auto p-5">

            <Heading className="text-2xl text-gray-800">

              Welcome!

            </Heading>

            <Text className="text-base text-gray-800">

              Hi {name}, thanks for signing up!

            </Text>

            <Button

              href={verificationUrl}

              className="bg-brand text-white px-5 py-3 rounded block text-center no-underline box-border"

            >

              Verify Email

            </Button>

          </Container>

        </Body>

      </Tailwind>

    </Html>

  );

}

// Preview props for testing

WelcomeEmail.PreviewProps = {

  name: 'John Doe',

  verificationUrl: 'https://example.com/verify/abc123'

} satisfies WelcomeEmailProps;

export { WelcomeEmail };

Behavioral Guidelines

When iterating over the code, only update what the user asked for. Keep the rest intact.

If the user asks to use media queries, inform them that most email clients don't support them and suggest a different approach.

Never use template variables (like {{name}}) directly in TypeScript code. Instead, reference the underlying properties directly. If the user explicitly asks for {{variableName}}, place the mustache string only in PreviewProps, never in the component JSX:

const EmailTemplate = (props) => {

  return (

    <h1>Hello, {props.variableName}!</h1>

  );

}

EmailTemplate.PreviewProps = {

  variableName: "{{variableName}}",

};

export default EmailTemplate;

Never write the {{variableName}} pattern directly in the component structure. If the user insists, explain that this would make the template invalid.

Essential Components

See references/COMPONENTS.md for complete component documentation.

Core Structure:

Html - Root wrapper with lang attribute

Head - Meta elements, styles, fonts

Body - Main content wrapper

Container - Outermost centering wrapper (has built-in max-width: 37.5em). Use only once per email.

Section - Interior content blocks (no built-in max-width). Use for grouping content inside Container.

Row & Column - Multi-column layouts

Tailwind - Enables Tailwind CSS utility classes

Content:

Preview - Inbox preview text, always first inside <Body>

Heading - h1-h6 headings

Text - Paragraphs

Button - Styled link buttons (always include box-border)

Link - Hyperlinks

Img - Images (see Static Files section below)

Hr - Horizontal dividers

Specialized:

CodeBlock - Syntax-highlighted code

CodeInline - Inline code

Markdown - Render markdown

Font - Custom web fonts

Before Writing Code

When a user requests an email template, ask clarifying questions FIRST if they haven't provided:

Brand colors - Ask for primary brand color (hex code like #007bff)

Logo - Ask if they have a logo file and its format (PNG/JPG only - warn if SVG/WEBP)

Style preference - Professional, casual, or minimal tone

Production URL - Where will static assets be hosted in production?

Static Files and Images

Directory Structure

Local images must be placed in the static folder inside your emails directory:

project/

├── emails/

│   ├── welcome.tsx

│   └── static/           <-- Images go here

│       └── logo.png

Dev vs Production URLs

Use this pattern for images that work in both dev preview and production:

const baseURL = process.env.NODE_ENV === "production"

  ? "https://cdn.example.com"  // User's production CDN

  : "";

export default function Email() {

  return (

    <Img

      src={`${baseURL}/static/logo.png`}

      alt="Logo"

      width="150"

      height="50"

    />

  );

}

How it works:

Development: baseURL is empty, so URL is /static/logo.png - served by React Email's dev server

Production: baseURL is the CDN domain, so URL is https://cdn.example.com/static/logo.png

Important: Always ask the user for their production hosting URL. Do not hardcode localhost:3000.

Styling

See references/STYLING.md for comprehensive styling documentation including typography, layout patterns, dark mode, and brand consistency.

Key Rules

Use Tailwind with pixelBasedPreset (email clients don't support rem). Import pixelBasedPreset from react-email.

Never use flexbox or grid — use Row/Column components or tables for layouts.

Avoid CSS/Tailwind media queries (sm:, md:, lg:, xl:) — limited email client support.

Never use theme selectors (dark:, light:) — not supported.

Never use SVG or WEBP images — warn users about rendering issues.

Always specify border type (border-solid, border-dashed, etc.) — email clients don't inherit it.

For single-side borders, reset others first (border-none border-l border-solid).

Required Classes

Component

Required Class

Why

Button

box-border

Prevents padding from overflowing the button width

Hr / any border

border-solid (or border-dashed, etc.)

Email clients don't inherit border type

Single-side borders

border-none + the side

Resets default borders on other sides

Structure Notes

Always define <Head /> inside <Tailwind> when using Tailwind CSS

<Preview> should always be the first element inside <Body>

Only include props in PreviewProps that the component actually uses

Use fixed width/height for known-size elements (logos, icons); responsive sizing (w-full, h-auto) for content images

Rendering

Convert to HTML

import { render } from 'react-email';

import { WelcomeEmail } from './emails/welcome';

const html = await render(

  <WelcomeEmail name="John" verificationUrl="https://example.com/verify" />

);

Convert to Plain Text

const text = await render(<WelcomeEmail name="John" verificationUrl="https://example.com/verify" />, { plainText: true });

Sending

React Email supports sending with any email service provider. See references/SENDING.md for complete sending documentation including Resend, Nodemailer, and SendGrid examples.

Quick example using the Resend SDK:

import { Resend } from 'resend';

import { WelcomeEmail } from './emails/welcome';

const resend = new Resend(process.env.RESEND_API_KEY);

const { data, error } = await resend.emails.send({

  from: 'Acme <onboarding@resend.dev>',

  to: ['user@example.com'],

  subject: 'Welcome to Acme',

  react: <WelcomeEmail name="John" verificationUrl="https://example.com/verify" />

});

The Resend Node SDK automatically handles both HTML and plain-text rendering.

CLI Commands

The react-email package provides a CLI accessible via the email command:

Command

Description

email dev --dir <path> --port <port>

Start the preview development server (default: ./emails, port 3000)

email build --dir <path>

Build the preview app for production deployment

email start

Run the built preview app

email export --outDir <path> --pretty --plainText --dir <path>

Export templates to static HTML files

email resend setup

Connect the CLI to your Resend account via API key

email resend reset

Remove the stored Resend API key

Internationalization

See references/I18N.md for complete i18n documentation. React Email supports three libraries: next-intl, react-i18next, and react-intl.

Email Editor

React Email includes a visual editor (@react-email/editor) that can be embedded in your app. It's built on TipTap/ProseMirror and produces email-ready HTML.

See references/EDITOR.md for complete documentation including:

EmailEditor — batteries-included component with bubble menus, slash commands, and theming

StarterKit — 35+ email-aware extensions (headings, lists, tables, columns, buttons, etc.)

Inspector — contextual sidebar for editing styles

EmailTheming — built-in themes (basic, minimal) with customizable CSS properties

composeReactEmail — export editor content to email-ready HTML and plain text

Custom extensions via EmailNode and EmailMark

Quick example:

import { EmailEditor, type EmailEditorRef } from '@react-email/editor';

import '@react-email/editor/themes/default.css';

import { useRef } from 'react';

export function MyEditor() {

  const ref = useRef<EmailEditorRef>(null);

  return (

    <EmailEditor

      ref={ref}

      content="<p>Start typing...</p>"

      theme="basic"

    />

  );

}