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Ad Ops Workflow · 8 min read · Specs Verified 2026

HTML5 Banner QC Checklist for Ad Ops & Agencies

Ad server rejections delay campaign launches and strain agency and client relationships. Before submitting display creatives to Google Ads, Campaign Manager 360, or DSPs, run through this definitive 12-point QC checklist.

The 12-Point Preflight QA Checklist

  1. Index.html Location: Is index.html located at the root of the ZIP file (not nested inside a folder)?
  2. clickTag Declaration: Is clickTag properly defined in standard JavaScript syntax in the <head> tag?
  3. Platform Limits: Is the ZIP within the booked platform limit (Google Ads: 600 KB and 40 files; CM360: 9.5 MB and 100 files)?
  4. Ad Size Meta Tag: Is <meta name="ad.size" content="width=300,height=250"> included in the HTML header?
  5. Backup Image: If the trafficking workflow calls for one, is a lightweight static JPG/PNG backup included?
  6. HTTPS SSL Compliance: Are all external calls (fonts/CDN scripts) using secure https:// URLs?
  7. Approved CDNs: Are external scripts hosted on Google approved library allowlists?
  8. Animation Duration: Does the animation loop cap at 30 seconds max?
  9. No Hardcoded URLs: Does the click listener call window.open(window.clickTag) without hardcoded destination landing pages?
  10. CPU Performance: Are CSS transforms hardware accelerated to prevent lag on lower end devices?
  11. No Local Storage Calls: Are localStorage or sessionStorage functions absent to comply with privacy policies?
  12. Cross Browser Sandbox Verification: Has the creative rendered cleanly in an isolated iframe?

Automate 90% of these checks in seconds by dragging your ZIP package directly into our HTML5 Banner Validator.