Website carbon estimates

This site publishes static HTML. The carbon tracker distinguishes browser measurements, a model based on those measurements, and things we have not measured. It does not claim carbon neutrality or a verified carbon saving.

This page load

The browser's Resource Timing and Navigation Timing APIs report transferred bytes for available first-party requests. We sum transferSize for this page and its first-party resources, then multiply by 148.2 g CO₂e per decimal GB. That factor is the sum of the rounded operational and embodied intensities in the Sustainable Web Design Model v4, multiplied by its default global grid intensity of 494 g CO₂e/kWh. No green-hosting discount or guessed cache/visitor ratio is applied.

This is an adaptation using observed transfer bytes, not a full SWDM per-visit audit. Cached resources can report zero transfer. Browser timing buffers are finite; missing or restricted entries are excluded. Third-party requests and activity inside external frames, server CPU, ongoing device use, publishing builds and the reader-stat service's own work are not measured. The tracker does not send browser transfer data to us or store it.

The last 24 hours

The backend reuses existing Turnstile-verified article sessions, retaining only a public aggregate. It counts unexpired sessions with activity in the preceding 24 hours, rather than all pageviews or unique people. A session spanning two daily windows can appear in both; expired records are not recovered. This is a rolling window, not a Sydney calendar day.

For each retained session we take that article's current minified HTML size, compressed with gzip at build time, and apply the same emissions factor. This estimates only the HTML associated with those retained reads. Images, fonts, CSS, JavaScript, video, API calls, homepage traffic, unverified readers, bots and older expired sessions are outside this daily figure. Gzip is a standardised reference; Cloudflare can serve a different encoding. The current article size may differ from its size when the read happened. This is neither a measured emissions total nor the site's full daily footprint.

The aggregate is cached for up to three minutes and refreshed on page load or when opening the tracker. If the database or reference file is unavailable, the tracker says so; it never substitutes demo traffic. No new reader tracking, cookies or database tables are added.

Static versus server-rendered sites

Static hosting still uses servers. It avoids rendering the article and querying a content database on each uncached request, but a dynamic site with an effective CDN cache can deliver the same bytes. This website also uses APIs for features such as reactions and reader statistics.

Daily savings are unmeasured, not zero. To estimate a defensible difference we need an equivalent dynamic site, matched traffic and assets, its origin cache-hit rate and energy use, and comparable hosting electricity factors. A transfer-based model cannot isolate PHP, database or CPU energy, so multiplying traffic by an arbitrary “static savings percentage” would mislead readers.

Read the model's assumptions and limitations and Green Web Foundation's model guidance. Detailed analytics remain private. See our reader statistics explanation and privacy policy.