Eleventy (11ty) contact form without a server

The thank-you page

After a successful submission the redirect field sends visitors to /thanks/. It has to be an absolute http(s) URL, which is why the include builds it from site.url. Without a redirect, Formlane uses the default redirect from your form settings, or its own hosted thank-you page.

If your site lives under a sub-path (for example a GitHub Pages project site at https://username.github.io/repo-name/), set url to that full address including the path.

Optional: stay on the page

If you'd rather show a message without a page change, send the form with fetch(). With Accept: application/json, Formlane answers {"success": true, "message": "Form submitted successfully", "id": "…"} or {"success": false, "error": "limit_reached", "message": "…"} with a 4xx/5xx status. message is always English, so the snippet shows its own text per error code. Append it to _includes/contact-form.html:

<script>
  const MESSAGES = {
    limit_reached: "This form can't take more messages this month. Please email us directly.",
    rate_limited: "Too many messages in a short time. Please try again in a few minutes.",
  };
  const form = document.querySelector('form[action*="formlane"]');
  if (form) form.addEventListener("submit", async (e) => {
    e.preventDefault();
    const res = await fetch(form.action, {
      method: "POST",
      headers: { Accept: "application/json" },
      body: new FormData(form),
    });
    const json = await res.json().catch(() => ({}));
    // Spam caught by the honeypot or the content rules also gets success: true.
    form.outerHTML = json.success
      ? "<p>Thanks! We'll get back to you.</p>"
      : "<p>" + (MESSAGES[json.error] || "Sorry, that didn't work. Please try again later.") + "</p>";
  });
</script>

Without JavaScript the plain form still works, so the script is a progressive enhancement, not a requirement.

Spam protection without a captcha

• Honeypot: the hidden botcheck checkbox. If a bot ticks it, Formlane returns a normal success response and stores nothing.
• Rate limit: 10 submissions per 10 minutes per visitor and form.
• Content rules: messages with 4 or more links, link markup or typical spam phrases go to a separate spam tab. Spam doesn't count toward your monthly limit.
• Allowed domains: limit the form to your own domain in its settings.

Limits worth knowing

• Up to 64 KB per submission, 50 fields and 10,000 characters per field.
• Content types: application/x-www-form-urlencoded, multipart/form-data (text fields only) and application/json.
• File uploads are not supported yet. If your form needs attachments, use one of the alternatives below.

Alternatives, honestly compared

Where the data is stored

Stored in Frankfurt, in a Supabase database in the eu-central-1 region. The app runs on Vercel: our server functions run in Frankfurt (fra1); static files and edge routing are served by Vercel's global network. All providers are listed in the privacy policy. Formlane is run by Mindcaptain Services OÜ in Tallinn, Estonia. A data processing agreement is included in the Terms (Art. 28 GDPR, smallwerk.com/dpa), and IP hashes are deleted after 30 days. Add the contact form to your own privacy policy, and delete old submissions in the dashboard when you no longer need them.

Pricing

Free: 250 submissions a month and up to 5 forms. Starter: $8/month for 2,500 submissions. Pro: $19/month for 25,000 submissions. Prices are in USD incl. VAT where applicable (also available in EUR). A read-only REST API and MCP server are included on every plan, including Free.

Related guides

• Contact form for any HTML site
• Hugo contact form
• GitHub Pages contact form
• Contact form spam without a captcha

FAQ