Un formulario para React sin crear servidor.

<form action="https://mailcontact.app/api/forms/your-form-id" method="POST" data-mailcontact-form lang="es" data-mailcontact-language="es">
  <input type="hidden" name="_language" value="es" />
  <fieldset>
    <legend>Contáctanos</legend>
    <label>
      Nombre (opcional)
      <input name="name" type="text" autocomplete="name" maxlength="200" />
    </label>
    <label>
      Correo electrónico
      <input name="email" type="email" autocomplete="email" maxlength="320" required />
    </label>
    <label>
      Mensaje
      <textarea name="message" rows="5" maxlength="5000" required></textarea>
    </label>
    <noscript>
    <div aria-hidden="true" style="position:absolute;left:-10000px;width:1px;height:1px;overflow:hidden;">
      <label>Sitio web
        <input name="company_website" type="text" tabindex="-1" autocomplete="off" />
      </label>
    </div>
    </noscript>
    <button type="submit">Enviar mensaje</button>
  </fieldset>
  <p data-contact-status role="status" aria-live="polite" aria-atomic="true"></p>
</form>
<script defer src="https://mailcontact.app/forms/v1.js" crossorigin="anonymous" referrerpolicy="no-referrer"></script>

import { useState } from "react";

export default function ContactForm() {
  const [status, setStatus] = useState<"idle" | "sending" | "sent" | "error">("idle");

  async function handleSubmit(event: React.FormEvent<HTMLFormElement>) {
    event.preventDefault();
    const data = new FormData(event.currentTarget);
    setStatus("sending");
    try {
      const res = await fetch("https://mailcontact.app/api/forms/your-form-id", {
        method: "POST",
        body: data,
      });
      setStatus(res.ok ? "sent" : "error");
    } catch {
      setStatus("error");
    }
  }

  if (status === "sent") {
    return <p>Thanks! Your message is on its way.</p>;
  }

  return (
    <form onSubmit={handleSubmit}>
      <input type="text" name="name" placeholder="Your name" />
      <input type="email" name="email" placeholder="[email protected]" required />
      <textarea name="message" placeholder="What's on your mind?" required />
      <button type="submit" disabled={status === "sending"}>
        {status === "sending" ? "Sending…" : "Send"}
      </button>
      {status === "error" && <p>Something went wrong. Please try again.</p>}
      <input name="company_website" type="text" tabIndex={-1} autoComplete="off"
        style={{ position: "absolute", left: "-10000px" }} aria-hidden="true" />
    </form>
  );
}