I used the code below in my zapier workflow to --- capture UTM info when a lead takes action on our website, fills out a form, then gets routed into pardot/salesforce. 

Steps:

1: webhook

2. code for UTMs
3. prospect routing through pardot/salesforce

I used for URL: http://site.com?utm_source=source&utm_campaign=campaign&utm_medium=medium&utm_term=term&utm_content=content

and the code I used: 

const url = inputData.url; // http://example.com?

const urlObject = new URL(url);

const id = urlObject.searchParams.get('id')

console.log(id)

// prints

const utm_term = urlObject.searchParams.get('utm_term');

const fbclid = urlObject.searchParams.get('fbclid');

const gclid = urlObject.searchParams.get('gclid');

const gacid = urlObject.searchParams.get('gacid');

const utm_campaign = urlObject.searchParams.get('utm_campaign');

const utm_content = urlObject.searchParams.get('utm_content');

const utm_medium = urlObject.searchParams.get('utm_medium');

const utm_source = urlObject.searchParams.get('utm_source');

output = {

"utm_term":utm_term,

"gclid":gclid,

"fbclid":fbclid,

"gacid":gacid,

"utm_source":utm_source,

"utm_campaign":utm_campaign,

"utm_medium":utm_medium,

"utm_content":utm_content,

};