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Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
92
GRADE
A
FIX
0
REVIEW
3
PASS
4
INFO
1
Device:
Mobile Desktop
Checks
8
4 PASS 3 REVIEW
B
CO2 Per Page Load
0.52g CO2 per view
REVIEW
0.52g CO2 per view
Info::
0.52g CO2 per page view
This page transfers 2.2 MB, producing an estimated 0.52g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.11g, end-user device 0.40g.
Got: 0.52g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 62.6 kg CO2/year
With 10,000 page views per month, this page would generate approximately 62.6 kg of CO2 annually — equivalent to charging 7824 smartphones.
Info::
Green hosting reduces data center emissions

0.52g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 58% of websites

Sustainable Web Design model v4 · Page size: 2.2 MB

Your site
0.52g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.11g
End-user device
0.40g
At 10,000 monthly views: Monthly: 5.2 kg · Annual: 62.6 kg · ≈ 7824 smartphone charges
B
Carbon Budget
42th percentile
REVIEW
42th percentile
Info::
0.52g CO2 — below the median website (0.60g)
Better than an estimated 58% of websites, but above the sustainability target of 0.50g. Reducing page weight would help reach the target.
Info::
Estimated 42th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.52g

42nd percentile

Cleaner than 58% of websites

✗ Above the median website

vs Median 13% cleaner ✓
vs Target 4% more
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Cloudflare CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
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 Not identified✗CDN Cloudflare✓

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 29 KB (vs 2256 KB first visit). 44 of 45 resources are served from browser cache, saving 0.51g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.52g)
First visit
2256 KB
Repeat visit
29 KB

99% reduction on repeat visits

Saving 0.51g CO2 per returning visitor

44 resources served from cache · 1 resources re-downloaded

A+
Transfer Efficiency
97% efficient
PASS
97% efficient
Info::
Transfer efficiency: 97%
Only 56 KB of potential savings identified. Your page is well-optimized for size.
97% efficient

Total waste: 56 KB (3% of page weight)

Unused JS 56 KB

0.01g unnecessary CO2 per visit

Actual transfer 2256 KB
Theoretical minimum 2200 KB
Potential savings 56 KB (0.01g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Web Font Weight Variants
1 font weights loaded across 1 famil(y/ies) -- reasonable
PASS
1 font weights loaded across 1 famil(y/ies) -- reasonable
Info::
1 font weight(s) loaded across 1 famil(y/ies)
Image Optimization
15 images, 1416 KB total, 90 KB wasted
INFO

Image Optimization Audit

Total Images

15

Total Size

1416 KB

Oversized

1

Wasted

90 KB

8 missing dimensions 1 missing lazy loading
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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