Send email from Next.js (App Router) with Nodemailer

npm install nodemailer

// .env.local
SMTP_HOST=smtp.queensmtp.com
SMTP_PORT=587
SMTP_USER=your-smtp-username
SMTP_PASS=your-smtp-password

// app/api/contact/route.ts
import nodemailer from "nodemailer";
import { NextResponse } from "next/server";

export const runtime = "nodejs";   // SMTP needs the Node runtime, not Edge

const transporter = nodemailer.createTransport({
  host: process.env.SMTP_HOST,
  port: Number(process.env.SMTP_PORT || 587),
  secure: Number(process.env.SMTP_PORT) === 465,
  auth: { user: process.env.SMTP_USER, pass: process.env.SMTP_PASS },
});

export async function POST(req: Request) {
  const { name, email, message } = await req.json();
  if (!email || !message) return NextResponse.json({ ok: false }, { status: 400 });

  await transporter.sendMail({
    from: '"Website" <hello@yourdomain.com>',   // your verified domain — NOT the visitor's address
    replyTo: email,
    to: "support@yourdomain.com",
    subject: `Contact form: ${name}`,
    text: message,
  });
  return NextResponse.json({ ok: true });
}