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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
4.08g CO2 per view
FIX
4.08g CO2 per view
Critical::
4.08g CO2 per page view
This page transfers 17.2 MB, producing an estimated 4.08g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.10g, network 0.84g, end-user device 3.13g.
Got: 4.08g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 489.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 489.7 kg of CO2 annually — equivalent to charging 61206 smartphones.
Info::
Green hosting reduces data center emissions

4.08g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 5% of websites

Sustainable Web Design model v4 · Page size: 17.2 MB

Your site
4.08g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.10g
Network
0.84g
End-user device
3.13g
At 10,000 monthly views: Monthly: 40.8 kg · Annual: 489.7 kg · ≈ 61206 smartphone charges
F
Carbon Budget
Action
95th percentile
FIX
95th percentile
Warning::
4.08g 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

4.08g

95th percentile

Cleaner than 5% of websites

✗ Above the median website

vs Median 580% more
vs Target 716% 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 155 KB (vs 17653 KB first visit). 135 of 138 resources are served from browser cache, saving 4.04g CO2 per repeat visit.
Info::
Repeat visit: 0.04g CO2 (first visit: 4.08g)
First visit
17653 KB
Repeat visit
155 KB

99% reduction on repeat visits

Saving 4.04g CO2 per returning visitor

135 resources served from cache · 3 resources re-downloaded

A+
Transfer Efficiency
98% efficient
PASS
98% efficient
Info::
Transfer efficiency: 98%
Only 297 KB of potential savings identified. Your page is well-optimized for size.
98% efficient

Total waste: 297 KB (2% of page weight)

Unused JS 297 KB

0.07g unnecessary CO2 per visit

Actual transfer 17653 KB
Theoretical minimum 17356 KB
Potential savings 297 KB (0.07g 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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