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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
84
GRADE
B
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
F
CO2 Per Page Load
Action
1.96g CO2 per view
FIX
1.96g CO2 per view
Warning::
1.96g CO2 per page view
This page transfers 8.3 MB, producing an estimated 1.96g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.05g, network 0.40g, end-user device 1.50g.
Got: 1.96g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 234.9 kg CO2/year
With 10,000 page views per month, this page would generate approximately 234.9 kg of CO2 annually — equivalent to charging 29362 smartphones.
Info::
Green hosting reduces data center emissions

1.96g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 12% of websites

Sustainable Web Design model v4 · Page size: 8.3 MB

Your site
1.96g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.05g
Network
0.40g
End-user device
1.50g
At 10,000 monthly views: Monthly: 19.6 kg · Annual: 234.9 kg · ≈ 29362 smartphone charges
F
Carbon Budget
Action
88th percentile
FIX
88th percentile
Warning::
1.96g CO2 — above the median website (0.60g)
Heavier than an estimated 12% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 88th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.96g

88th percentile

Cleaner than 12% of websites

✗ Above the median website

vs Median 226% more
vs Target 292% more
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 8468 KB first visit). 90 of 94 resources are served from browser cache, saving 1.95g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.96g)
First visit
8468 KB
Repeat visit
27 KB

100% reduction on repeat visits

Saving 1.95g CO2 per returning visitor

90 resources served from cache · 4 resources re-downloaded

A+
Transfer Efficiency
92% efficient
PASS
92% efficient
Info::
Transfer efficiency: 92%
Only 641 KB of potential savings identified. Your page is well-optimized for size.
92% efficient

Total waste: 641 KB (8% of page weight)

Unused JS 641 KB

0.15g unnecessary CO2 per visit

Actual transfer 8468 KB
Theoretical minimum 7827 KB
Potential savings 641 KB (0.15g 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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