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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
66
GRADE
D
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
F
CO2 Per Page Load
Action
9.29g CO2 per view
FIX
9.29g CO2 per view
Critical::
9.29g CO2 per page view
This page transfers 39.3 MB, producing an estimated 9.29g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.23g, network 1.92g, end-user device 7.14g.
Got: 9.29g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 1115.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 1115.1 kg of CO2 annually — equivalent to charging 139384 smartphones.
Info::
Green hosting reduces data center emissions

9.29g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 39.3 MB

Your site
9.29g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.23g
Network
1.92g
End-user device
7.14g
At 10,000 monthly views: Monthly: 92.9 kg · Annual: 1115.1 kg · ≈ 139384 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
9.29g 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

9.29g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 1449% more
vs Target 1758% more
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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 88 KB (vs 40202 KB first visit). 213 of 214 resources are served from browser cache, saving 9.27g CO2 per repeat visit.
Info::
Repeat visit: 0.02g CO2 (first visit: 9.29g)
First visit
40202 KB
Repeat visit
88 KB

100% reduction on repeat visits

Saving 9.27g CO2 per returning visitor

213 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 926 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 926 KB (2% of page weight)

Unused JS 926 KB

0.21g unnecessary CO2 per visit

Actual transfer 40202 KB
Theoretical minimum 39275 KB
Potential savings 926 KB (0.21g CO2)

See Deep Analysis sections above for specific optimizations.

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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