How can I pass Marketo lead info from an email to a webpage?

[Brandon_der_Bla]

I have the following use case: I'm sending an email through Marketo to several leads. A link in the email will point them to one of the pages on my website. When they get to the page I will use the Marketo API to prefill a form with their information (or simply verify that they clicked the link) and then once they're identified provide them with a download link. How can I pass lead information from the email to the website (assuming a new browser session without cookies or anything like that). It looks like using mkto_tok is the wrong approach from what I've researched so far.

Additional information: We're using the Marketo API and our own HTML forms so we have more freedom over how they're built.

[SanfordWhiteman · Accepted solution]

When they get to the page I will use the Marketo API to prefill a form with their information

Please do not do this. Your API limit is not high enough (nor is the endpoint performant enough, but that's another matter) to be used in response to individual end user activities. You will simply be opening a DoS vulnerability against this and all your other API integrations.

You need only use the API-free and infinitely scalable Pre-Fill technique here: Form Pre-Fill. External sites. No limits. You're welcome. This can be used with any form, not just a Marketo form.

As for your specific question "pass Marketo lead info" you can add any tokens you want to the query string. But I don't get the point. If all your data is on the lead already, it doesn't need to be "passed". Just send a tracked link from Marketo, the appended mkt_tok takes care of the rest.

[Brandon_der_Bla]

Your API limit is not high enough (nor is the endpoint performant enough, but that's another matter) to be used in response to individual end user activities.

So does this mean we shouldn't use the API even for submitting forms? My team wants to build custom forms from scratch so we have more control over the design, but does that mean we have to have a dummy embedded form next to it to hook into Marketo?

[SanfordWhiteman]

So does this mean we shouldn't use the API even for submitting forms?

Yes, that's exactly what it means. There are no upsides, only minor-to-colossal downsides.

but does that mean we have to have a dummy embedded form next to it to hook into Marketo?

I wouldn't say "next to it" -- the hidden embedded form need not be in any particular place in the DOM.