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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
62
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
3.99g CO2 per view
FIX
3.99g CO2 per view
Critical::
3.99g CO2 per page view
This page transfers 16.9 MB, producing an estimated 3.99g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.83g, end-user device 3.07g.
Got: 3.99g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 479.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 479.3 kg of CO2 annually — equivalent to charging 59910 smartphones.
Info::
Green hosting reduces data center emissions

3.99g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 16.9 MB

Your site
3.99g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.83g
End-user device
3.07g
At 10,000 monthly views: Monthly: 39.9 kg · Annual: 479.3 kg · ≈ 59910 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
3.99g 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

3.99g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 566% more
vs Target 699% more
B
Transfer Efficiency
79% efficient
REVIEW
79% efficient
Info::
Transfer efficiency: 79%
An estimated 3665 KB (21%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 3665 KB of unused JavaScript. This wasted data produces 0.85g of unnecessary CO2 per page view.
79% efficient

Total waste: 3665 KB (21% of page weight)

Unused JS 3665 KB

0.85g unnecessary CO2 per visit

Actual transfer 17279 KB
Theoretical minimum 13614 KB
Potential savings 3665 KB (0.85g 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 121 KB (vs 17279 KB first visit). 471 of 502 resources are served from browser cache, saving 3.97g CO2 per repeat visit.
Info::
Repeat visit: 0.03g CO2 (first visit: 3.99g)
First visit
17279 KB
Repeat visit
121 KB

99% reduction on repeat visits

Saving 3.97g CO2 per returning visitor

471 resources served from cache · 31 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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