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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
80
GRADE
B
FIX
2
REVIEW
0
PASS
4
INFO
0
Device:
Mobile Desktop
Checks
6
4 PASS 2 FIX
D
CO2 Per Page Load
Action
1.04g CO2 per view
FIX
1.04g CO2 per view
Warning::
1.04g CO2 per page view
This page transfers 4.4 MB, producing an estimated 1.04g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.03g, network 0.22g, end-user device 0.80g.
Got: 1.04g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 125.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 125.3 kg of CO2 annually — equivalent to charging 15665 smartphones.
Info::
Green hosting reduces data center emissions

1.04g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 38% of websites

Sustainable Web Design model v4 · Page size: 4.4 MB

Your site
1.04g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.03g
Network
0.22g
End-user device
0.80g
At 10,000 monthly views: Monthly: 10.4 kg · Annual: 125.3 kg · ≈ 15665 smartphone charges
D
Carbon Budget
Action
62th percentile
FIX
62th percentile
Warning::
1.04g CO2 — above the median website (0.60g)
Heavier than an estimated 38% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 62th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

1.04g

62nd percentile

Cleaner than 38% of websites

✗ Above the median website

vs Median 74% more
vs Target 109% 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
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 58 KB (vs 4518 KB first visit). 94 of 95 resources are served from browser cache, saving 1.03g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 1.04g)
First visit
4518 KB
Repeat visit
58 KB

99% reduction on repeat visits

Saving 1.03g CO2 per returning visitor

94 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
94% efficient
PASS
94% efficient
Info::
Transfer efficiency: 94%
Only 278 KB of potential savings identified. Your page is well-optimized for size.
94% efficient

Total waste: 278 KB (6% of page weight)

Unused JS 278 KB

0.06g unnecessary CO2 per visit

Actual transfer 4518 KB
Theoretical minimum 4239 KB
Potential savings 278 KB (0.06g 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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