HTML5 banner checker
Inspect an HTML5 creative ZIP for entry HTML, declared dimensions, clickTag declarations, missing local assets, and insecure URLs.
Start with a general static check or the Campaign Manager 360 profile. The creative is read as files and is never run.
Your inputs stay in this browser tab. Files and tags are processed in an isolated workspace, without advertising or analytics scripts.
How to use it
- Choose a ZIP and the profile that matches your handoff. ZIPs stay on your device.
- If there is more than one HTML file, choose the intended entry file and run the check again.
- Resolve file errors, review warnings in context, and test rendering and clicks in the target platform.
Worked example · sample data
The entry file declares 300 × 250 and contains a clickTag variable, but references images/logo.png that is absent from the ZIP. The first two checks pass; the missing asset is an error. A clickTag declaration alone does not confirm that the click works.
Before you use the result
This is a static inspection, not a browser preview or a platform approval test. It cannot confirm rendering, animation, click behavior, runtime requests, or macros.
The CM360 profile checks selected documented packaging rules. The ad.size meta tag is optional in CM360; a missing declaration is a warning. Google Web Designer exits and dynamically constructed paths need manual review.
Inspection limits: 10 MiB compressed, 32 MiB expanded, 500 entries, and 8 MiB per file. Only ordinary stored or Deflate ZIP files are supported. CM360’s separate documented limit is 100 files and 10 MB.
Rules checked against the linked CM360 guidance on October 9, 2026. A publisher may impose additional requirements.
Reference: Google: prepare HTML5 assets for Campaign Manager 360