VAST macros / Ad and pod
[UNIVERSALADID] VAST macro
Short answer: The creative's UniversalAdId (registry and value). Introduced in VAST 4.1.
What it means
Resolves to the UniversalAdId that uniquely identifies the creative across systems, in the form registry value. Used for creative-level frequency capping and reporting.
Example value
After the player substitutes the macro, [UNIVERSALADID] becomes something like:
ad-id.org%204AB12345Where it is valid
Impression and tracking URLs.
Macros are case-sensitive and substituted only inside URL fields. A macro written in the wrong case, or placed where it has no defined value, is sent to the server as literal text instead of a value.
Using it in a tag
<Impression><![CDATA[https://t.example.com/i?val=[UNIVERSALADID]&cb=[CACHEBUSTING]]]></Impression>VAST XML fragment only. This excerpt belongs inside a complete VAST document, so standalone validation will fail until it is wrapped in a full <VAST>response.
Related vastlint rules
- VAST-2.0-macro-unknown: URL contains a [MACRO] that is not a recognised IAB VAST macro
- VAST-2.0-macro-lowercase: Recognised macro is not uppercase — players match macro names case-sensitively
- VAST-2.0-macro-uri-unencoded: Macro-bearing URL contains characters that must be percent-encoded per RFC 3986
Related macros
- [ADSERVINGID]: The unique ad-serving identifier shared across the supply chain.
- [TRANSACTIONID]: A unique identifier for this ad request transaction.
Validate your macros
vastlint flags unknown, mis-cased, deprecated, out-of-context, and unencoded macros in any tracking, click, error, impression, or media URL:
# CLI: exits non-zero on errors, ideal for pipelines
vastlint check creative.xmlUse the right tool for this failure
If you already have the resolved XML, run a pure spec check. If you only have a live tag URL, test that endpoint first. If the failure happens in the wrapper chain, inspect each hop.