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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
76
GRADE
C
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
1.19g CO2 per view
FIX
1.19g CO2 per view
Warning::
1.19g CO2 per page view
This page transfers 5.0 MB, producing an estimated 1.19g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.25g, end-user device 0.91g.
Got: 1.19g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 142.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 142.4 kg of CO2 annually — equivalent to charging 17796 smartphones.
Info::
Green hosting reduces data center emissions

1.19g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 34% of websites

Sustainable Web Design model v4 · Page size: 5.0 MB

Your site
1.19g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.25g
End-user device
0.91g
At 10,000 monthly views: Monthly: 11.9 kg · Annual: 142.4 kg · ≈ 17796 smartphone charges
D
Carbon Budget
Action
66th percentile
FIX
66th percentile
Warning::
1.19g CO2 — above the median website (0.60g)
Heavier than an estimated 34% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 66th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.19g

66th percentile

Cleaner than 34% of websites

✗ Above the median website

vs Median 98% more
vs Target 137% more
B
Transfer Efficiency
87% efficient
REVIEW
87% efficient
Info::
Transfer efficiency: 87%
An estimated 662 KB (13%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 662 KB of unused JavaScript. This wasted data produces 0.15g of unnecessary CO2 per page view.
87% efficient

Total waste: 662 KB (13% of page weight)

Unused JS 662 KB

0.15g unnecessary CO2 per visit

Actual transfer 5133 KB
Theoretical minimum 4470 KB
Potential savings 662 KB (0.15g 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 Cloudflare✓CDN 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 33 KB (vs 5133 KB first visit). 146 of 148 resources are served from browser cache, saving 1.18g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.19g)
First visit
5133 KB
Repeat visit
33 KB

99% reduction on repeat visits

Saving 1.18g CO2 per returning visitor

146 resources served from cache · 2 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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