Key Concepts

Table of contents

  1. Introduction
  2. How Zuko works
  3. Key terms
    1. visitor
    2. session
    3. slug
    4. domain
    5. forms
    6. fields
    7. events
    8. custom attributes
    9. custom events


Zuko is a SaaS platform designed to help you understand how your website visitors are interacting with your online forms, surveys and checkouts.

How Zuko works

Zuko works by tracking your site visitors when they:

  • View your form
  • Interact with your form’s fields
  • Successfully complete your form

Zuko tracks these events by adding a tracking JavaScript to your web page. Zuko does not track your visitor’s data that they enter into your form, but simply that they are entering data and how they are interacting with the form.

From the data that we collect, we calculate the metrics that enable you to discover the issues that your visitors encounter whilst interacting with your forms. This data is made available through the Zuko app.

Key terms


A visitor is someone who interacts with your form and is given a unique ID. Their unique ID is persisted across all forms on the same domain.


A session represents a period of activity from when a visitor first views your form, then interacts with it, to when they either complete the form or stop interacting with the form.


A slug is a unique identifier for your form on your domain. When events are sent to the Zuko platform, they include the slug and domain from where the event originates. When combined, slug and domain form a unique identifier for a form on the Zuko platform.


The domain that Zuko uses is the domain that your site is on, ignoring subdomains.

Here are some examples of URLs and the domain that will be used by Zuko:

URL Hostname Domain


Any standard HTML element can be tracked as a form in Zuko.


Zuko tracks interactions on these types of HTML elements:


Along with a field’s tagName, Zuko records three optional HTML attributes for each field: type, name and id.

It is important that your fields can be identified by a combination of the field’s tagName and these three HTML attributes. Your account manager will then help to label your fields to easily view them in the Zuko app.


Zuko tracks the following standard event types on your fields:

  • change
  • click
  • input
  • paste
  • keydown
  • focusin
  • focusout

custom attributes

Zuko allows you to assign attributes to a visitor’s session. You can then compare segments of visitors, and explore certain behaviours and outcomes across segments.

By default, Zuko will automatically detect and track two attributes for you:

  • browserFamily The browser that the visitor used to interact with the form
  • deviceType The device type that the visitor used to interact with the form

You also have the ability to push any information you collect about your visitors into the platform. An attribute is a piece of information about a visitor. Custom attributes are intended to segment your form’s sessions, they are not intended to be used for identifiers.

Examples of custom attributes are:

  • visitorSource e.g. email, market_campaign
  • existingCustomer e.g. true, false
  • campaignRef e.g. testA, testB

custom events

Visitors will encounter specific types of events when interacting with your form. For example, they may encounter field errors or see promotional messages.

Zuko can track these custom events as and when they occur throughout a visitor’s session. Even if they occur multiple times for the same event type, you can send as many custom events as you need.

Custom events are sent simply as a short string to describe the event type.

Examples of custom events are:

  • Email field: email invalid
  • Promotion: 20% discount code
  • Error_email-field-is-invalid