The Artifact Machine Website Carbon Calculator

A small artifact for estimating CO2 emissions per page load using the Website Carbon API with a local calculation fallback.

Use this Actor to measure the carbon footprint of a webpage, surface page weight concerns, and check green hosting status. It gives teams a quick sustainability signal alongside their standard performance audits.

Pulled from The Artifact Machine: generated, tested, and cleaned up by a human.

What It Checks

• estimated CO2 in grams per page view (first visit)
• estimated annual CO2 at 10,000 monthly visits
• energy consumption per page load in kilowatt-hours
• green hosting indicator
• transferred page size in bytes, KB, and MB
• compression status (gzip, brotli, deflate, zstd)
• page weight rating from A+ to F based on the Sustainable Web Design model

Best For

• sustainability and ESG reporting
• page weight benchmarking
• green hosting verification
• performance budget monitoring
• agency client sustainability audits

Input

{
  "url": "https://example.com"
}

Input Fields

• url: the page URL to estimate carbon emissions for.

Output

The Actor writes one dataset item and an OUTPUT key-value record with:

• URL, CO2 per view, CO2 per year, energy per load, green host flag
• page size and weight details
• carbon rating and grade
• estimation method (API or local fallback)

Example output fields:

• url: the target URL
• co2PerLoad: CO2 in grams per page view
• co2PerYear: estimated annual CO2 in kg at 10k monthly visits
• energyPerLoad: energy in kWh per page view
• greenHost: whether the host reports using renewable energy
• pageSize: transferred bytes
• pageWeight: human-readable weight breakdown
• rating: A+ to F carbon efficiency grade
• score: 0-100 carbon score
• issues: actionable performance and carbon recommendations

Limits

• This Actor estimates carbon based on transferred bytes, not CPU rendering energy.
• The Website Carbon API is free and rate-limited. If the API is unreachable, the Actor falls back to local calculation using the Sustainable Web Design model.
• Estimates assume 10,000 monthly page views for annual projections — adjust interpretation for high- or low-traffic sites.
• Some sites block automated requests differently from regular browsers; results should be reviewed before client delivery.

Pricing

Use pay-per-event pricing based on completed reports rather than per issue. Suggested starting price: $1.00 to $2.00 per completed carbon estimate after private runtime cost is measured.