Tracking Snippet

• Captures UTM parameters and fbclid from the URL, the Meta pixel cookies _fbp / _fbc, the landing page and the referrer.
• Remembers them in first-party storage on your domain, so they survive multi-step funnels, page reloads and booking pages on a subdomain.
• Passes them on to your opt-in forms and to Typeform, Cal.com and Calendly links and embeds, so they reach Hermon with the opt-in.

Paste this tag into the <head> of every page in your funnel, replacing the key with your workspace’s public key (it starts with pk_live_).

<script src="https://cdn.hermon.io/s/v1.js" data-key="pk_live_your_public_key"></script>

Optional attributes

These are the exact names the snippet uses. Empty values are left out. When you create hidden fields in a page builder, Typeform or Cal.com, use these names.

• The first touch is recorded on the visitor’s first visit and never changes.
• The last touch is replaced only when the visitor arrives on a URL that carries utm_* or fbclid. Normal page-to-page navigation does not change it.
• Hermon receives the last touch, falling back to the first touch. Both are available through hermon.getAttribution().

Step-by-step setup per platform: Platform setup.

For custom forms and single-page apps that send the opt-in themselves.

// Stored first-touch and last-touch values
hermon.getAttribution();
// → { public_key, first_touch: {...}, last_touch: {...} }

// Flat map of the fields above, ready to submit with a custom form
hermon.getFields();
// → { utm_source: "facebook", fbclid: "IwAR...", hermon_pk: "pk_live_...", ... }

hermon.debug(true);   // turn on console logging for this session
hermon.version;       // e.g. "1.0.0"

// Safe to call before the script has loaded
window.hermon = window.hermon || [];
hermon.push(function (h) {
  console.log(h.getFields());
});

• Open your funnel with ?utm_source=test&hermon_debug=1 and open the browser console. You will see what was captured, stored and injected. Debug mode stays on for the browser session; ?hermon_debug=0 turns it off.
• In production, watch the click ID coverage on the Meta Conversions API health panel in Hermon: the share of opt-ins that arrive with a Meta click ID.

s/v1.js always serves the latest 1.x release, so fixes reach your pages within minutes without changing your install. Breaking changes ship as a new major version (s/v2.js) and never replace v1. To pin an exact version, use s/1.0.0.js. See the changelog.

• Nothing in the console in debug mode — the tag is missing on that page, or the key is invalid (debug mode prints a warning).
• Values missing in Typeform or Cal.com — the hidden fields / hidden booking questions are not created with the exact field names.
• A form inside an iframe from another domain cannot be reached by the snippet. Use that tool’s hidden-field setup.
• Buttons that navigate with JavaScript instead of a normal link are not decorated. Use an <a href> link or the embed.
• Content Security Policy — if your site sends a CSP header, allow https://cdn.hermon.io in script-src.
• Attribution dropped — if the hermon_pk sent with an opt-in belongs to another workspace, Hermon still creates the lead but ignores its traffic data. Check that the key in the tag is your own.