How to create an embeddable HTML form?

SendFox gives every form a one-line embed snippet you paste onto any website to start collecting subscribers. Here’s how to build a form, style it, choose how it appears, and grab the code.

Overview

The recommended embed is a single auto-updating loader script. You paste it once, and it always renders the latest version of your form — theme, fields, and display mode included — so anything you change in the builder shows up everywhere without re-pasting. When a visitor submits, the contact is added straight to the list you chose. Free accounts can create one form; Lifetime and Pro accounts can create more.

Prefer to watch? This short video covers the whole flow:

Create your form

1. From the top nav, open Growth → Forms.
2. Click Create Form. The builder opens with four tabs: Form, Design, Display, and Settings.
3. On the Form tab, add the fields you want to collect and set your button text.
4. On the Settings tab, choose the list(s) new subscribers should join under Add signups to lists (at least one list is required), and optionally add a redirect URL to send subscribers to your own thank-you page after they submit.
5. Click Publish form. You’re taken straight to the embed page with your code and share link.

Get and embed the code

On the embed page, find the Add it to your website card (marked Recommended) and click Copy code. The snippet looks like this:

<script src="https://sendfox.com/js/embed.js" data-form="your-form-slug" data-api="https://sendfox.com" async></script>

1. Copy the one-line script from the Add it to your website card.
2. Paste it into your website where you want the form to appear — it works with WordPress, Squarespace, Webflow, and any HTML page.

That’s it — anyone who submits the form is added to your SendFox list automatically. Because the snippet loads your form live, editing the form in the builder updates it everywhere it’s embedded, with no need to re-paste.

Choose how the form appears

The one snippet drives all four display modes. Pick one on the Display tab, under Display mode:

• Inline — the form renders where you paste the snippet, in your page content.
• Popup — centered over the page.
• Slide-in — a corner card, less intrusive.
• Sticky bar — pinned to the top edge. The sticky bar keeps to a single row, so it collects email only; your other fields still show on the hosted page and in the other display modes.

For Popup, Slide-in, and Sticky bar, you also choose a trigger under Show it when:

• Visitor has been on the page for a set number of seconds (time-on-page delay).
• Visitor scrolls past a set percentage of the page.
• Visitor is about to leave (exit intent).
• Visitor clicks a link or button — any element on your page with the class sendfox-open opens the form.

Under Frequency, you can set “if dismissed, don’t show again for N days.” The form also never shows again to someone after a successful signup. Inline forms have no trigger — they simply render in place.

Style the form on the Design tab

Styling now happens in the builder, not by hand-editing embed HTML. On the Design tab you can:

• Pick a ready-made color template (Classic, Ink, Coral pop, and more).
• Set the Button, Button text, Background, and Text colors from the swatches, or choose a custom color.
• Adjust the Corner radius slider to round the edges.

Your styling travels with the loader snippet, so it applies everywhere the form is embedded and updates live when you change it.

No website? Share a link

Every form also has a hosted page that renders it exactly as designed — great for link-in-bio and social posts. On the embed page, use the No website? Share a link card and click Copy link to grab the URL.

Legacy HTML embed (still supported)

If you prefer the older pasted-HTML method, expand Prefer the legacy HTML embed? on the embed page and click Copy legacy code. This gives you the raw form markup plus the SendFox form.js script. It still works, but it won’t pick up theme or display-mode changes you make in the builder — you’d re-copy it after each edit. If you go this route and want to hand-style the markup, see How can I format my SendFox HTML form? For most sites, the one-line loader snippet above is the better choice.

Troubleshooting

The form says it’s “not enabled for this website”

• You’ll see: “This form is not enabled for this website. If you own the form, add this domain to its allowed embed domains in SendFox.” This happens when the form has an embed-domain allowlist that doesn’t include the site you pasted it on. Open the form, go to the Settings tab, and add the site’s domain under Allowed embed domains. An allowlist is required only when Invisible reCAPTCHA is turned on.

I edited the form but my site still shows the old one

• If you used the recommended one-line loader snippet, changes apply automatically — try a hard refresh to clear your browser cache. If you used the legacy HTML embed, re-copy the code after saving and replace the old snippet on your site.

Adding a redirect URL won’t save

• The redirect URL must be a full link starting with http:// or https:// (for example, https://example.com/thanks).

Still need help? Reach us through the Help Center.

Frequently asked questions

Where do I find the embed code?

On the form’s embed page, which opens automatically after you publish the form. The one-line snippet is in the Add it to your website card.

Can I embed the same form in more than one place?

Yes — paste the same snippet on as many pages as you like; all submissions flow into the same list.

Can I send subscribers to my own page after they sign up?

Yes — in the builder’s Settings tab, add your thank-you page’s full URL as the redirect. After someone subscribes, SendFox sends them there.

Can I add custom fields like phone or city?

Yes — add them on the Form tab. See Can I add custom fields to my form?