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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
2.19g CO2 per view
FIX
2.19g CO2 per view
Critical::
2.19g CO2 per page view
This page transfers 9.3 MB, producing an estimated 2.19g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.45g, end-user device 1.68g.
Got: 2.19g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 262.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 262.9 kg of CO2 annually — equivalent to charging 32868 smartphones.
Info::
Green hosting reduces data center emissions

2.19g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 9.3 MB

Your site
2.19g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.45g
End-user device
1.68g
At 10,000 monthly views: Monthly: 21.9 kg · Annual: 262.9 kg · ≈ 32868 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
2.19g 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

2.19g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 265% more
vs Target 338% more
B
Transfer Efficiency
89% efficient
REVIEW
89% efficient
Info::
Transfer efficiency: 89%
An estimated 1030 KB (11%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 1030 KB of unused JavaScript. This wasted data produces 0.24g of unnecessary CO2 per page view.
89% efficient

Total waste: 1030 KB (11% of page weight)

Unused JS 1030 KB

0.24g unnecessary CO2 per visit

Actual transfer 9480 KB
Theoretical minimum 8449 KB
Potential savings 1030 KB (0.24g 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
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 27 KB (vs 9480 KB first visit). 57 of 58 resources are served from browser cache, saving 2.18g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 2.19g)
First visit
9480 KB
Repeat visit
27 KB

100% reduction on repeat visits

Saving 2.18g CO2 per returning visitor

57 resources served from cache · 1 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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