System Library variables

Built-in answers about the responder's context and state.

Overview of the System Library

System Library variables allow access to built-in attributes about the responder's environment or context. They allow you to reach into the internals of Formsort, or the responder's browser, and pull out information that may be useful to you, like user device or OS, or the label of the variant the user is visiting.

These variables will automatically be sent along with your answers to any integrations/configurations you have set up, and do not need to be added in-flow in any way. They can, of course, be templated using variable templating, or used in conditional logic statements at your discretion.

Available answer definitions

current group ID

The ID of the current Group the user is in (falling back to the Group Index if a Group ID has not been set).

current step ID

The ID of the current step (falling back to the current step index if an ID is not set). The Step ID is useful to include if using any analytics integrations, in order to analyze step-level performance. This id can be manually set in the Step Settings.

current step index

The index of the current step, which is the number automatically assigned to the step according to where it is in the flow (e.g. first step is step "0", second step is step "1", etc.). The step index cannot be manually set.

current step URL

The URL for the current step, including the page index (https://{flow-url}#1 for the first step of a page).

If "Use step ID instead of index" is enabled in Variant Settings, the current step URL will instead look like https://{flow-url}#step-id.

expected redirect url

Where is the user getting redirected?

Will be set even if not currently redirecting: this is where the responder would be redirected at any point in the flow.

When the flow is being finalized, this is the same as the URL they were finally redirected to.

flow label

The string label identifying the flow that was loaded.

Formsort environment

Which environment is the responder in?


This variable will include the base flow url in the answer payload.

is Android?

Is the responder on an Android device?

Useful as a condition for displaying an Play Store link if you have an app.

is iOS?

Is the responder on an iOS device, such as an iPhone?

Useful as a condition for displaying an App Store link if you have an app.

is Mac OS?

Is the responder on Mac OS?

is mobile

Is the responder on a mobile device, regardless of manufacturer?

is returning responder

Has the responder been to this flow before?

is Windows?

Is the responder on Windows OS?

Jornaya lead ID

The Jornaya lead ID. Will only be set if you are using the Jornaya integration in the active environment.

previous step url

The URL of the previous step, useful for back links.


The URL that form user arrived from, corresponding to document.referrer.

May be undefined if the user navigated directly to the flow, or if the referring page does not send the referrer per their Content Security Policy.

Take care with collecting the referrer: it may contain personally-identifying information, if the referring page puts user data in its own URL and does not have a Content Security Policy defined.

responder UUID

The responder uuid of the responder.

session UUID

The UUID of the session, unique for every time a flow is loaded. Reloading the browser or navigating back to the page will create a new UUID.

Trusted Form certificate URL

The URL of the Trusted Form certificate issued for the session. Read more about the Trusted Form integration here.

user agent

Navigator user agent, meaning the browser the responder is using. Includes version number.

variant label

The string label identifying the variant that was loaded.

variant revision UUID

The UUID of the variant revision that was loaded for the responder.

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