Gatsby contact form �Formspree alternative with AI spam filtering

Contact form for a Gatsby site, posting JSON to SmartForm AI.

What you're POSTing

The endpoint accepts a standard HTML form POST or JSON via AJAX. Two kinds of fields:

Your form fields â€?name, email, message, whatever you want. Every non-reserved field lands in your dashboard as a column in the submissions table.

Reserved fields â€?names starting with _ are interpreted by the API, not stored:

Field	Purpose
_gotcha	Honeypot. Keep it empty. Hidden from humans via CSS; bots fill it automatically. Any non-empty value silently drops the submission. Add this to every form.
_hp_email / _website / _url / _phone	Honeypot aliases for _gotcha (WordPress / WPForms / Contact Form 7 migrations). Same drop semantics.
_next	Same-origin URL to redirect to after a successful submission. Browser POST results in a 302 here. AJAX calls (with Accept: application/json) get the same value back as next_url in the JSON response. Only http(s) and in-site paths allowed.
_subject	Override the AI-generated email subject line. Max 200 chars; control characters stripped.
X-Gotcha header	Same as _gotcha for JSON requests where you can't add a hidden form field.

Field names are Formspree-compatible â€?migrating from formspree.io/f/{form_id} requires no renaming.

Setup

1. Get a form ID at https://usesmartform.com/dashboard.
2. Clone, install, configure, run:

   git clone https://github.com/smartformai/smartform-example-gatsby.git
   cd smartform-example-gatsby
   npm install
   # edit gatsby-config.js �siteMetadata.smartformFormId
   npm run develop

3. Open http://localhost:8000/contact, submit, check your dashboard.

The form

src/pages/contact.js is a static React page that hosts the contact form.

import React, { useState } from 'react';

const FORM_ID  = 'f_replace_me';   // <-- from your dashboard
const ENDPOINT = 'https://api.usesmartform.com/api/v1/f';

export default function Contact() {
  const [status, setStatus] = useState('');

  async function onSubmit(e) {
    e.preventDefault();
    setStatus('Sending�);
    const data = Object.fromEntries(new FormData(e.currentTarget));
    try {
      const r = await fetch(`${ENDPOINT}/${FORM_ID}`, {
        method:  'POST',
        headers: { 'Content-Type': 'application/json', 'Accept': 'application/json' },
        body:    JSON.stringify(data),
      });
      const body = await r.json();
      setStatus(`Sent! submission_id=${body.submission_id} intent=${body.intent}`);
    } catch (err) {
      setStatus(`Error: ${err.message}`);
    }
  }

  return (
    <main style={{ font: '16px/1.4 system-ui', maxWidth: 480, margin: '40px auto' }}>
      <h1>Contact</h1>
      <form onSubmit={onSubmit} style={{ display: 'grid', gap: 12 }}>
        <input name="name"  placeholder="Name"  required />
        <input name="email" type="email" placeholder="Email" required />
        <textarea name="message" placeholder="Message" required style={{ minHeight: 100 }} />
        <input type="text" name="_gotcha" tabIndex={-1} autoComplete="off"
               style={{ position: 'absolute', left: -9999 }} aria-hidden />
        <button type="submit" style={{ background: '#7c3aed', color: '#fff', border: 0, padding: '8px 10px' }}>
          Send
        </button>
        <p>{status}</p>
      </form>
    </main>
  );
}

How the API works

• POST {endpoint}/api/v1/f/{form_id} â€?JSON or form-data, no API key.
• Response: { success, message, submission_id, is_spam, intent, next_url }.

For the full contract, see https://usesmartform.com/docs.

Deploy

npm run build         # static output in ./public
# Push ./public to Netlify / Cloudflare Pages / GitHub Pages

FAQ

Is there a free tier?

Yes. AI spam filtering is enabled by default on every plan. AI intent classification and high-value lead detection require a paid plan (Pro or Business) �the dashboard enforces this and returns HTTP 402 if you try to enable them on a free workspace.

Do I need an API key?

No. The form posts directly to a public endpoint using only an 8-char form ID, which is non-enumerable. The example also includes a hidden _gotcha honeypot field so naive bots cannot submit.

Does it work with SSG?

Yes. Gatsby builds static HTML at build time and the form posts straight from the browser to the public endpoint.

Related examples

Next.js contact form | Astro contact form | Nuxt contact form

License

MIT.