vastlint

VPAID-width-height-missing

VPAID <MediaFile> missing width or height attribute

WarningAttributesIAB VPAID 2.0 §3.1, VAST 2.0 §3.9

A VPAID is missing the or attribute (or both). VPAID 2.0 requires these attributes so the player knows how much space to allocate for the ad unit before it initialises. Without them, players may render the unit at the wrong size, behind other elements, or not at all. This is separate from the deprecation issue — it is a spec violation on any VAST version.

Why this matters in production

Treat this as a migration and compatibility warning. VPAID issues often survive desktop QA and then fail silently on mobile, CTV, or SSAI paths. Attribute rules are where VPAID integrations break most often. The unit may be present, but a wrong type, casing, or dimension value prevents correct initialization.

How to fix

Add width and height attributes to the VPAID <MediaFile> element matching the intended ad unit dimensions in pixels.

Invalid

<MediaFile delivery="progressive" type="application/javascript"
           apiFramework="VPAID">
  <![CDATA[https://example.com/vpaid.js]]>
</MediaFile>

Valid

<MediaFile delivery="progressive" type="application/javascript"
           apiFramework="VPAID" width="1280" height="720">
  <![CDATA[https://example.com/vpaid.js]]>
</MediaFile>
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Other Attributes rules

VPAID-type-invalidVPAID <MediaFile> type must be application/javascript or application/x-javascriptVPAID-apiframework-casingapiFramework value is not the canonical "VPAID" (wrong case)
← All VPAID rulesSIMID rules (migration target) →