Microsoft's demand and supply platform, formerly AppNexus and then Xandr. Serves hosted HTML5 creatives from a single ZIP and supplies the click destination as a clickTag query parameter on the ad URL, which the creative reads at runtime.
Also known as Xandr, Microsoft Advertising, Microsoft Invest, Microsoft Monetize, Xandr Invest, AppNexus, Invest, Monetize, AppNexus.
| Category | DSP |
|---|---|
| Regions | US, EU, GLOBAL |
| Maximum ZIP size | No stated cap |
| Entry file | index.html |
| ZIP structure | Entry file must sit at the ZIP root |
| Ad size meta tag | Optional |
| Required markup | Xandr requires index.html to be a complete document including the html, head and body elements. |
| External assets | External assets allowed |
| Secure references | Every external reference must be served over HTTPS |
| Click method | clickTag on the ad URL |
| Click variable | clickTag |
| Click URL query parameter | clickTag |
| Click URL at export | Left empty — the platform sets it when the ad is trafficked |
| Multiple click destinations | One click area per banner |
Official requirements Also from Xandr (Microsoft Advertising): HTML5 creative guidelines and specifications, Use IAB's HTML5 clickTag standard on Xandr, Troubleshoot creatives (creative setup analysis).
This is the click declaration Foldwrap writes into an HTML5 export for Xandr (Microsoft Advertising), with a placeholder destination. Copy it into your own creative if you are hand-building the banner.
var clickTag = (function () { var m = new RegExp('[?&]' + "clickTag" + '=([^&]*)', 'i').exec(window.location.search); return m ? decodeURIComponent(m[1]) : "https://www.example.com/landing"; })();Xandr (Microsoft Advertising) sets the destination at trafficking time, so an empty value in the exported file is correct and expected.
These are the rules Foldwrap checks a package against before it is delivered to Xandr (Microsoft Advertising). Each is derived from the requirements above, so a constraint Xandr (Microsoft Advertising) does not state is not checked and is not listed.
Foldwrap runs these checks on every package it exports for Xandr (Microsoft Advertising), and names the creative and the constraint when one fails.
Every figure above, with the document it came from and the date we read it.
The ad URL returned to a publisher's page includes a `clickTag` parameter in the query string. Ad developers who prefer not to use Xandr' `getClickTag()` convenience can access the `clickTag` parameter's value with their own Javascript. In this case, the ad does not need to load the Xandr HTML5 Library.
learn.microsoft.com · retrieved 21 September 2026
<a href="javascript:void(0)" onClick="window.open(APPNEXUS.getClickTag(), '_blank');">
learn.microsoft.com · retrieved 21 September 2026
To serve on the Microsoft Advertising platform and other third-party platforms, all HTML5 creatives must adhere to the guidelines and specifications listed here, our creative standards, and any other guidelines that may apply.
learn.microsoft.com · retrieved 21 September 2026 · likely
The zip file must contain an **index.html** file that resides at the root of the zip file and not in a subfolder.
learn.microsoft.com · retrieved 21 September 2026
The **index.html** file should be a complete and valid HTML document that includes the `<html>`, `<head>`, and `<body>` entities.
learn.microsoft.com · retrieved 21 September 2026
All hosted HTML5 creatives must be uploaded in a single zip file. The zip file must contain an index.html file that resides at the root of the zip file and not in a subfolder. The index.html file should be a complete and valid HTML document that includes the html, head, and body entities. The clickTag parameter must be referenced in the URL of all HTML5 creatives.
learn.microsoft.com · retrieved 21 September 2026 · likely
<script type="text/javascript" src="https://acdn.adnxs.com/html5-lib/1.4.1/appnexus-html5-lib.min.js"></script>
learn.microsoft.com · retrieved 21 September 2026 · likely
Only secure content is supported.
learn.microsoft.com · retrieved 21 September 2026
Creatives may not use local shared objects (LSOs). ... LSOs include Flash cookies, browser helper objects, and HTML5 Local Storage.
learn.microsoft.com · retrieved 21 September 2026
Compare every platform side by side, or produce a Xandr (Microsoft Advertising)-ready bundle from an approved Figma design with Foldwrap.