GTM Ultimate Stack
Find everything that reads a GTM variable before you change it
Search a variable to list every tag, trigger and variable that reads it, follow chains through lookup tables, and know what a change to its value will reach.
Variables are shared
One variable can feed dozens of items. A Measurement ID constant is read by every GA4 tag. A dataLayer variable feeds a tag, a trigger condition and a lookup table. Change how it's built and every one of them changes with it.
Search it, read the used-by list
Search the variable and choose it. The upstream side lists everything that uses it: tags whose settings reference it, triggers whose conditions read it, and other variables built on it. That list is everything a change to it reaches directly.
A map centred on a constant variable used by three tags shown by name, a lookup table and nine more tags.
Follow chains through lookup tables
Some variables read other variables. A lookup table that maps page types to content groups reads a dataLayer variable, and a configuration tag reads the lookup table. Click the lookup table to see what reads it in turn, and keep following until you reach the tags.
A three-step chain: a dataLayer variable, a lookup table that reads it, and a configuration tag that reads the lookup table.
Renaming a variable
Before you rename a variable, search it. The used-by list is what to check afterwards: in the preview, and in GTM before you publish. Roll out a naming convention covers bulk renames.
Built-ins count too
Before you switch off a built-in variable such as Click Classes, search it. If anything uses it, it's still needed.
Questions about variable impact
Why isn't every tag that reads the ID in the export?
A lineage export follows a shared variable one step, not out to every other tag that uses it. Search the variable itself to see all of them.
Does the map show the variable's value?
No. It shows what uses it. Values are set in GTM and on your site.
Can a variable be used by something the map doesn't show?
Tag sequencing and Trigger Group membership aren't drawn, but neither works through variables. Every {{Name}} reference is drawn.
ODDVX for Windows
Know what a change touches.
Map any GTM account on Free. Premium adds lineage export and email, plus several accounts per run in every other GTM module.