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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
73
GRADE
C
FIX
2
REVIEW
2
PASS
2
INFO
0
Device:
Mobile Desktop
Checks
6
2 PASS 2 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.89g CO2 per view
FIX
0.89g CO2 per view
Info::
0.89g CO2 per page view
This page transfers 3.8 MB, producing an estimated 0.89g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.18g, end-user device 0.68g.
Got: 0.89g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 106.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 106.7 kg of CO2 annually — equivalent to charging 13336 smartphones.
Info::
Green hosting reduces data center emissions

0.89g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 42% of websites

Sustainable Web Design model v4 · Page size: 3.8 MB

Your site
0.89g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.18g
End-user device
0.68g
At 10,000 monthly views: Monthly: 8.9 kg · Annual: 106.7 kg · ≈ 13336 smartphone charges
D
Carbon Budget
Action
58th percentile
FIX
58th percentile
Warning::
0.89g CO2 — above the median website (0.60g)
Heavier than an estimated 42% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 58th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.89g

58th percentile

Cleaner than 42% of websites

✗ Above the median website

vs Median 48% more
vs Target 78% more
B
Transfer Efficiency
85% efficient
REVIEW
85% efficient
Info::
Transfer efficiency: 85%
An estimated 577 KB (15%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 577 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
85% efficient

Total waste: 577 KB (15% of page weight)

Unused JS 577 KB

0.13g unnecessary CO2 per visit

Actual transfer 3846 KB
Theoretical minimum 3268 KB
Potential savings 577 KB (0.13g CO2)

See Deep Analysis sections above for specific optimizations.

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Cloudflare CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
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 Not identified✗CDN Cloudflare✓

Cloudflare: 100% renewable energy for global network since 2019

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 65 KB (vs 3846 KB first visit). 299 of 304 resources are served from browser cache, saving 0.87g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 0.89g)
First visit
3846 KB
Repeat visit
65 KB

98% reduction on repeat visits

Saving 0.87g CO2 per returning visitor

299 resources served from cache · 5 resources re-downloaded

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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