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Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
83
GRADE
B
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.12g CO2 per view
FIX
1.12g CO2 per view
Warning::
1.12g CO2 per page view
This page transfers 4.7 MB, producing an estimated 1.12g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.23g, end-user device 0.86g.
Got: 1.12g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 133.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 133.9 kg of CO2 annually — equivalent to charging 16736 smartphones.
Info::
Green hosting reduces data center emissions

1.12g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 36% of websites

Sustainable Web Design model v4 · Page size: 4.7 MB

Your site
1.12g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.23g
End-user device
0.86g
At 10,000 monthly views: Monthly: 11.2 kg · Annual: 133.9 kg · ≈ 16736 smartphone charges
D
Carbon Budget
Action
64th percentile
FIX
64th percentile
Warning::
1.12g CO2 — above the median website (0.60g)
Heavier than an estimated 36% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 64th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.12g

64th percentile

Cleaner than 36% of websites

✗ Above the median website

vs Median 86% more
vs Target 123% more
C
Transfer Efficiency
Action
67% efficient
REVIEW
67% efficient
Warning::
Transfer efficiency: 67%
An estimated 1598 KB (33%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1598 KB of unused JavaScript. This wasted data produces 0.37g of unnecessary CO2 per page view.
67% efficient

Total waste: 1598 KB (33% of page weight)

Unused JS 1598 KB

0.37g unnecessary CO2 per visit

Actual transfer 4827 KB
Theoretical minimum 3228 KB
Potential savings 1598 KB (0.37g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Google Cloud, CDN: Cloudflare
Info::
Google Cloud: Verified by the Green Web Foundation
Info::
Cloudflare: 100% renewable energy for global network since 2019
Info::
Green hosting status based on known provider commitments
Green hosting detection uses a curated database of provider renewable energy commitments. This is not a real-time verification. For authoritative checks, visit thegreenwebfoundation.org.
Green Hosting✓ Green Hosted
Hosting Google Cloud✓CDN Cloudflare✓

Google Cloud: Verified by the Green Web Foundation

Cloudflare: 100% renewable energy for global network since 2019

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
97% cached
PASS
97% cached
Info::
97% reduction on repeat visits
Returning visitors download only 162 KB (vs 4827 KB first visit). 505 of 527 resources are served from browser cache, saving 1.08g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 1.12g)
First visit
4827 KB
Repeat visit
162 KB

97% reduction on repeat visits

Saving 1.08g CO2 per returning visitor

505 resources served from cache · 22 resources re-downloaded

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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