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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
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
1.27g CO2 per view
FIX
1.27g CO2 per view
Warning::
1.27g CO2 per page view
This page transfers 5.4 MB, producing an estimated 1.27g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.26g, end-user device 0.98g.
Got: 1.27g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 152.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 152.4 kg of CO2 annually — equivalent to charging 19047 smartphones.
Info::
Green hosting reduces data center emissions

1.27g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 31% of websites

Sustainable Web Design model v4 · Page size: 5.4 MB

Your site
1.27g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.26g
End-user device
0.98g
At 10,000 monthly views: Monthly: 12.7 kg · Annual: 152.4 kg · ≈ 19047 smartphone charges
D
Carbon Budget
Action
69th percentile
FIX
69th percentile
Warning::
1.27g CO2 — above the median website (0.60g)
Heavier than an estimated 31% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 69th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.27g

69th percentile

Cleaner than 31% of websites

✗ Above the median website

vs Median 112% more
vs Target 154% more
C
Transfer Efficiency
Action
72% efficient
REVIEW
72% efficient
Warning::
Transfer efficiency: 72%
An estimated 1563 KB (28%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1563 KB of unused JavaScript. This wasted data produces 0.36g of unnecessary CO2 per page view.
72% efficient

Total waste: 1563 KB (28% of page weight)

Unused JS 1563 KB

0.36g unnecessary CO2 per visit

Actual transfer 5493 KB
Theoretical minimum 3930 KB
Potential savings 1563 KB (0.36g 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
95% cached
PASS
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 251 KB (vs 5493 KB first visit). 283 of 303 resources are served from browser cache, saving 1.21g CO2 per repeat visit.
Info::
Repeat visit: 0.06g CO2 (first visit: 1.27g)
First visit
5493 KB
Repeat visit
251 KB

95% reduction on repeat visits

Saving 1.21g CO2 per returning visitor

283 resources served from cache · 20 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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