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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
65
GRADE
D
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
F
CO2 Per Page Load
Action
2.41g CO2 per view
FIX
2.41g CO2 per view
Critical::
2.41g CO2 per page view
This page transfers 10.2 MB, producing an estimated 2.41g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.06g, network 0.50g, end-user device 1.85g.
Got: 2.41g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 289.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 289.3 kg of CO2 annually — equivalent to charging 36161 smartphones.
Info::
Green hosting reduces data center emissions

2.41g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 10.2 MB

Your site
2.41g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.06g
Network
0.50g
End-user device
1.85g
At 10,000 monthly views: Monthly: 24.1 kg · Annual: 289.3 kg · ≈ 36161 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.41g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

2.41g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 302% more
vs Target 382% more
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 2293 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 2293 KB of unused JavaScript. This wasted data produces 0.53g of unnecessary CO2 per page view.
78% efficient

Total waste: 2293 KB (22% of page weight)

Unused JS 2293 KB

0.53g unnecessary CO2 per visit

Actual transfer 10429 KB
Theoretical minimum 8136 KB
Potential savings 2293 KB (0.53g 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: Amazon Web Services, CDN: Cloudflare
Info::
Amazon Web Services: 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 Amazon Web Services✓CDN Cloudflare✓

Amazon Web Services: 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
98% cached
PASS
98% cached
Info::
98% reduction on repeat visits
Returning visitors download only 174 KB (vs 10429 KB first visit). 52 of 54 resources are served from browser cache, saving 2.37g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 2.41g)
First visit
10429 KB
Repeat visit
174 KB

98% reduction on repeat visits

Saving 2.37g CO2 per returning visitor

52 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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