We Measured Every Analytics Script. Here Is What We Found.
We downloaded the main analytics scripts from every major provider — directly from their production CDNs. Not from documentation pages. Not from marketing claims. The actual minified, gzipped files that load on your visitors' browsers.
The raw numbers
| Tool | Size (gzipped) |
|---|---|
| SealMetrics | 1.3 KB |
| Plausible | 1.3 KB |
| Fathom | 1.9 KB |
| Simple Analytics | 3.8 KB |
| Mixpanel | 29.8 KB |
| PostHog | 56.4 KB |
| Matomo | 65.2 KB |
| Google Analytics 4 | 129.6 KB |
| Adobe Analytics | 150.7 KB |
GA4 is 99x heavier than SealMetrics. Adobe Analytics is 115x heavier.
What these numbers actually mean
For a site with 100,000 monthly visitors, GA4's script alone consumes 12.9 GB of bandwidth per month. SealMetrics consumes 130 MB. That is not a rounding error — it is a 99x difference in network resources, battery drain, and page load time.
53% of mobile users abandon sites that take more than 3 seconds to load. Heavy analytics scripts contribute directly to that latency through Total Blocking Time, Interaction to Next Paint delays, and bandwidth competition with your actual content.
Why are enterprise scripts so heavy?
Enterprise analytics tools carry legacy code for features that are now either illegal under GDPR or blocked by browsers. Cross-site tracking, third-party cookie management, fingerprinting modules — your visitors pay the performance cost for features you can not legally use.
The environmental cost
At 1 million pageviews per month, GA4's script generates approximately 30 kg of CO₂ annually — equivalent to driving 120 km. SealMetrics' equivalent: 0.3 kg, or about 1.2 km.
Data transfer consumes energy. The lighter the script, the lower the environmental footprint. At scale, the difference is significant.
How we measured
We downloaded scripts directly from production CDNs — the same files that load on real visitor browsers. We measured minified file sizes and applied standard gzip compression for consistency across all tools. No marketing claims, no documentation numbers. Just the actual bytes.
The bottom line
The script that measures your site performance is itself degrading your site performance. A 1.3 KB script captures 100% of traffic, complies with GDPR by design, and loads in under 50ms. The question is not whether you can afford to switch — it is whether you can afford not to. Calculate how much data you are losing.