Cloudflare Zaraz: Tag Management Without JavaScript | Ron Kopelman

Tag Management Reimagined From the CDN

Cloudflare Zaraz takes a radically different approach to traditional tag management. Instead of injecting JavaScript into the user’s browser (as GTM does), Zaraz intercepts events at the edge (Cloudflare’s CDN servers) and sends data directly to marketing platforms from the server.

The result: no third-party scripts load in the browser. Requests to Google Analytics, Meta, TikTok, or other platforms are executed by Cloudflare, not by the visitor’s browser. It is native server-side tracking without additional infrastructure to manage.

How Zaraz Differs From GTM

With Google Tag Manager, each added tag means additional JavaScript in the browser: collection scripts, conversion pixels, remarketing tags. On an average e-commerce site, you easily reach 15 to 30 third-party scripts, adding between 500 KB and 2 MB of JavaScript.

Zaraz eliminates this overhead. The browser sends a single lightweight call to the Cloudflare server, which then distributes data to the various platforms. The performance gain is measurable: Largest Contentful Paint reduction of 30 to 50% on heavily tagged sites, and near-total elimination of layout shift caused by third-party scripts.

Free With Cloudflare: The Business Model

Zaraz is included free in all Cloudflare plans, including the Free plan. This is a considerable advantage over managed sGTM solutions like Stape or Addingwell that charge per request volume.

The trade-off: your site must be proxied through Cloudflare (DNS in orange proxy mode). If your infrastructure already runs on Cloudflare, activating Zaraz is immediate. Otherwise, the DNS migration is a prerequisite that may be a barrier for some organizations.

Limitations and Restricted Ecosystem

Despite its strengths, Zaraz has important limitations to be aware of:

Smaller integration ecosystem than GTM. Major platforms (GA4, Meta, Google Ads) are covered, but niche or specialized tools are often missing.
No Community Template Gallery comparable to GTM’s. Custom integrations require development via Cloudflare’s Workers API.
More complex debugging: no equivalent to GTM Preview Mode with the same granularity. Debugging is done via Zaraz logs or Workers Logs.
Cloudflare dependency: your tracking stack is tied to your CDN, creating tight coupling.

Google Tag Gateway and Convergence

Interestingly, Cloudflare has integrated support for Google Tag Gateway, allowing you to use Zaraz as a proxy for Google tags while keeping your existing GTM configuration. This hybrid approach lets you benefit from Zaraz’s performance gains without abandoning the GTM ecosystem.

When Is Zaraz the Right Choice?

Zaraz is ideal for sites already on Cloudflare with a simple tracking stack (GA4, a few ad pixels) and strong performance requirements. Media sites, landing pages, and brochure websites benefit the most. For complex configurations with dozens of tags, advanced conditional triggers, and a need for a rich ecosystem, GTM Server-Side remains the go-to solution.