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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
1.26g CO2 per view
FIX
1.26g CO2 per view
Warning::
1.26g CO2 per page view
This page transfers 5.3 MB, producing an estimated 1.26g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.26g, end-user device 0.97g.
Got: 1.26g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 151.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 151.7 kg of CO2 annually — equivalent to charging 18964 smartphones.
Info::
Green hosting reduces data center emissions

1.26g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 32% of websites

Sustainable Web Design model v4 · Page size: 5.3 MB

Your site
1.26g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.26g
End-user device
0.97g
At 10,000 monthly views: Monthly: 12.6 kg · Annual: 151.7 kg · ≈ 18964 smartphone charges
D
Carbon Budget
Action
68th percentile
FIX
68th percentile
Warning::
1.26g CO2 — above the median website (0.60g)
Heavier than an estimated 32% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 68th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.26g

68th percentile

Cleaner than 32% of websites

✗ Above the median website

vs Median 111% more
vs Target 153% more
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 1203 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1203 KB of unused JavaScript. This wasted data produces 0.28g of unnecessary CO2 per page view.
78% efficient

Total waste: 1203 KB (22% of page weight)

Unused JS 1203 KB

0.28g unnecessary CO2 per visit

Actual transfer 5469 KB
Theoretical minimum 4266 KB
Potential savings 1203 KB (0.28g 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: Axis12 Ltd, CDN: Fastly
Info::
Axis12 Ltd: Verified by the Green Web Foundation
Info::
Fastly: 100% renewable energy for edge network
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 Axis12 Ltd✓CDN Fastly✓

Axis12 Ltd: Verified by the Green Web Foundation

Fastly: 100% renewable energy for edge network

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 54 KB (vs 5469 KB first visit). 129 of 133 resources are served from browser cache, saving 1.25g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.26g)
First visit
5469 KB
Repeat visit
54 KB

99% reduction on repeat visits

Saving 1.25g CO2 per returning visitor

129 resources served from cache · 4 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: Axis12 Ltd

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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