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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
72
GRADE
C
FIX
2
REVIEW
1
PASS
3
INFO
0
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
1.83g CO2 per view
FIX
1.83g CO2 per view
Warning::
1.83g CO2 per page view
This page transfers 7.7 MB, producing an estimated 1.83g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.38g, end-user device 1.40g.
Got: 1.83g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 219.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 219.4 kg of CO2 annually — equivalent to charging 27428 smartphones.
Info::
Green hosting reduces data center emissions

1.83g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 15% of websites

Sustainable Web Design model v4 · Page size: 7.7 MB

Your site
1.83g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.38g
End-user device
1.40g
At 10,000 monthly views: Monthly: 18.3 kg · Annual: 219.4 kg · ≈ 27428 smartphone charges
F
Carbon Budget
Action
85th percentile
FIX
85th percentile
Warning::
1.83g CO2 — above the median website (0.60g)
Heavier than an estimated 15% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 85th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.83g

85th percentile

Cleaner than 15% of websites

Above the median website

vs Median 205% more
vs Target 266% more
B
Transfer Efficiency
89% efficient
REVIEW
89% efficient
Info::
Transfer efficiency: 89%
An estimated 893 KB (11%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 893 KB of unused JavaScript. This wasted data produces 0.21g of unnecessary CO2 per page view.
89% efficient

Total waste: 893 KB (11% of page weight)

Unused JS 893 KB

0.21g unnecessary CO2 per visit

Actual transfer 7910 KB
Theoretical minimum 7017 KB
Potential savings 893 KB (0.21g 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: Cloudflare, CDN: Cloudflare
Info::
Cloudflare: 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 CloudflareCDN Cloudflare

Cloudflare: 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
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 302 KB (vs 7910 KB first visit). 331 of 336 resources are served from browser cache, saving 1.76g CO2 per repeat visit.
Info::
Repeat visit: 0.07g CO2 (first visit: 1.83g)
First visit
7910 KB
Repeat visit
302 KB

96% reduction on repeat visits

Saving 1.76g CO2 per returning visitor

331 resources served from cache · 5 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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