How much of the web is just advertising?

Enter a domain - see the megabytes of advertising and tracking it loads, which blockers/trackers are behind it and the CO₂ emissions it costs the environment.

Add a site if results are missing. Refreshed monthly.

Check a site

Type a domain to weigh its ads and trackers

In seconds: the advertising and tracking megabytes a page loads, the vendors behind them, and the CO₂ that data costs.

This is a business-oriented result page.
Did you know?

Digital advertising is enormous — and a lot of it is never even seen.

€118.9 bn
was spent on digital advertising in Europe in a single year.
57%
of every ad euro never becomes working media.
76%
of display ads worldwide are ever actually seen.
70%
in Europe, even fewer display ads are seen.
62%
of an ad’s carbon fires even when it’s blocked or unseen.
2×
the carbon of an ad on a “made-for-advertising” site vs trusted news.
16.8%
of ad spend buys impressions no one can even measure.
How to read this

Most of the weight isn’t the page — it’s what’s watching you read it.

We separate the bytes a page spends on advertising and tracking — ad servers, exchanges, tag managers, consent tools, social pixels — from the bytes it spends on the actual content. The checker shows you that ad share, the vendors behind it, and the carbon that data costs per million pageviews.

Common questions

Ad-carbon, explained

How heavy is the advertising on a typical website?

Across the homepages we measure, advertising and tracking add an average of about 5,244 g of CO₂ per million pageviews — and just over half of that weight is tracking and tag managers rather than the ads themselves.

What’s the difference between advertising and tracking on a website?

Advertising is the ad-serving stack — ad servers and exchanges. Tracking is the analytics, tag managers, consent tools and social pixels that record how you use the page. The checker separates the two so you can see how much of the weight is hidden tracking.

Does online advertising really produce CO₂?

Yes — every ad and tracker a page loads is data that has to be transferred and processed, which uses electricity. Per million pageviews, a heavy site’s ad stack can run to tens of kilograms of CO₂ a year.

Is the Ad-Carbon Checker free to use?

Yes — you can look up websites without signing up, and verifying your email lifts the daily limit.

Want to get more insights? Read our blog.

Discover trends, statistics and relevant facts in sustainable browsing — across privacy, ad blocking and media tracking.

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