---
title: User signup flow
description: Handle user registration with automated welcome emails and email verification using secure tokens.
image: https://developers.cloudflare.com/dev-products-preview.png
---

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# User signup flow

Send welcome and verification emails during user signup with secure token-based email verification.

This example demonstrates a complete user registration system with welcome emails and email verification.

Configure the email binding and KV namespaces in your Wrangler configuration file:

* [  wrangler.jsonc ](#tab-panel-8857)
* [  wrangler.toml ](#tab-panel-8858)

JSONC

```
{  "send_email": [{ "name": "EMAIL" }],  "kv_namespaces": [    { "binding": "USERS", "id": "<USERS_KV_NAMESPACE_ID>" },    {      "binding": "VERIFICATION_TOKENS",      "id": "<VERIFICATION_TOKENS_KV_NAMESPACE_ID>",    },  ],  "vars": {    "DOMAIN": "yourdomain.com",    "COMPANY_NAME": "Acme Inc.",  },}
```

TOML

```
[[send_email]]name = "EMAIL"
[[kv_namespaces]]binding = "USERS"id = "<USERS_KV_NAMESPACE_ID>"
[[kv_namespaces]]binding = "VERIFICATION_TOKENS"id = "<VERIFICATION_TOKENS_KV_NAMESPACE_ID>"
[vars]DOMAIN = "yourdomain.com"COMPANY_NAME = "Acme Inc."
```

The Worker exposes two routes: `POST /signup` creates a user, stores it in KV, and sends both a welcome email and a verification email containing a tokenized link; `GET /verify` validates that token and marks the user verified. The following code implements both handlers.

TypeScript

```
interface Env {  EMAIL: SendEmail;  USERS: KVNamespace;  VERIFICATION_TOKENS: KVNamespace;  DOMAIN: string;  COMPANY_NAME: string;}
interface User {  id: string;  email: string;  firstName: string;  verified: boolean;  createdAt: string;}
export default {  async fetch(request: Request, env: Env): Promise<Response> {    const url = new URL(request.url);
    if (url.pathname === "/signup" && request.method === "POST") {      return handleSignup(request, env);    }
    if (url.pathname === "/verify" && request.method === "GET") {      return handleVerification(request, env);    }
    return new Response("Not Found", { status: 404 });  },};
async function handleSignup(request: Request, env: Env): Promise<Response> {  const { email, firstName } = await request.json();
  // Validate and check for existing user  if (!email || !firstName || !isValidEmail(email)) {    return new Response(JSON.stringify({ error: "Invalid input" }), {      status: 400,    });  }
  if (await env.USERS.get(email)) {    return new Response(JSON.stringify({ error: "User already exists" }), {      status: 409,    });  }
  // Create user  const userId = crypto.randomUUID();  const user: User = {    id: userId,    email,    firstName,    verified: false,    createdAt: new Date().toISOString(),  };
  await env.USERS.put(email, JSON.stringify(user));
  // Generate verification token (expires in 1 hour)  const verificationToken = crypto.randomUUID();  await env.VERIFICATION_TOKENS.put(verificationToken, email, {    expirationTtl: 3600,  });
  // Send welcome email  await env.EMAIL.send({    to: email,    from: `noreply@${env.DOMAIN}`,    subject: `Welcome to ${env.COMPANY_NAME}!`,    html: `      <h1>Welcome ${firstName}!</h1>      <p>Thanks for joining ${env.COMPANY_NAME}. Please verify your email to get started.</p>    `,  });
  // Send verification email  const verificationUrl = `https://${env.DOMAIN}/verify?token=${verificationToken}`;  await env.EMAIL.send({    to: email,    from: `noreply@${env.DOMAIN}`,    subject: "Please verify your email address",    html: `      <h1>Verify Your Email</h1>      <p>Hi ${firstName}! Click the link below to verify your email:</p>      <a href="https://developers.cloudflare.com/email-service/examples/email-sending/signup-flow/%3C/span%3E%3Cspan%20style="--0:#89DDFF;--1:#007474">${verificationUrl}" style="background: #007bff; color: white; padding: 12px 24px; text-decoration: none; border-radius: 4px;">Verify Email</a>      <p>This link expires in 1 hour.</p>    `,  });
  return new Response(    JSON.stringify({      success: true,      message: "Account created. Please check your email.",      userId,    }),    { status: 201 },  );}
async function handleVerification(  request: Request,  env: Env,): Promise<Response> {  const url = new URL(request.url);  const token = url.searchParams.get("token");
  if (!token) {    return new Response("Missing token", { status: 400 });  }
  // Verify token  const userEmail = await env.VERIFICATION_TOKENS.get(token);  if (!userEmail) {    return new Response("Invalid or expired token", { status: 400 });  }
  // Get and update user  const userData = await env.USERS.get(userEmail);  if (!userData) {    return new Response("User not found", { status: 404 });  }
  const user: User = JSON.parse(userData);  user.verified = true;
  await env.USERS.put(user.email, JSON.stringify(user));  await env.VERIFICATION_TOKENS.delete(token);
  return new Response(    `    <html>      <body style="font-family: Arial, sans-serif; text-align: center; padding: 50px;">        <h1>Email Verified!</h1>        <p>Welcome ${user.firstName}! Your account is now active.</p>        <a href="https://developers.cloudflare.com/" style="background: #28a745; color: white; padding: 12px 24px; text-decoration: none; border-radius: 4px;">Continue</a>      </body>    </html>  `,    {      headers: { "Content-Type": "text/html" },    },  );}
function isValidEmail(email: string): boolean {  return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);}
```

## Next steps

* [Magic link authentication](https://developers.cloudflare.com/email-service/examples/email-sending/magic-link/) — passwordless login flow using a similar token pattern.
* [Send method](https://developers.cloudflare.com/email-service/api/send-emails/workers-api/) — full reference for the `send()` method.
* [Deliverability](https://developers.cloudflare.com/email-service/concepts/deliverability/) — keep verification emails out of spam folders.

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