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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
95
GRADE
A
FIX
0
REVIEW
2
PASS
5
INFO
1
Checks
8
5 PASS 2 REVIEW
B
Web Font Weight Variants
6 font weights loaded across 2 famil(y/ies)
REVIEW
6 font weights loaded across 2 famil(y/ies)
Info::
6 font weights loaded -- review whether all are used
5+ weights for a single page is often more than needed. Compare against the actual font-weight CSS rules in your stylesheets; trim weights that aren't applied to any element. Affected families: Merriweather, Source Sans 3.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
CO2 Per Page Load
0.16g CO2 per view
PASS
0.16g CO2 per view
Info::
0.16g CO2 per page view
This page transfers 0.7 MB, producing an estimated 0.16g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.03g, end-user device 0.12g.
Got: 0.16g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 18.8 kg CO2/year
With 10,000 page views per month, this page would generate approximately 18.8 kg of CO2 annually — equivalent to charging 2354 smartphones.
Info::
Green hosting reduces data center emissions

0.16g

Carbon Footprint per page view

✓ Below sustainability target (0.50g)

Cleaner than 90% of websites

Sustainable Web Design model v4 · Page size: 0.7 MB

Your site
0.16g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.00g
Network
0.03g
End-user device
0.12g
At 10,000 monthly views: Monthly: 1.6 kg · Annual: 18.8 kg · ≈ 2354 smartphone charges
A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Netlify CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Netlify: Hosted on AWS/Google Cloud with renewable energy matching
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 Netlify✓

Netlify: Hosted on AWS/Google Cloud with renewable energy matching

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 8 KB (vs 678 KB first visit). 13 of 14 resources are served from browser cache, saving 0.15g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.16g)
First visit
678 KB
Repeat visit
8 KB

99% reduction on repeat visits

Saving 0.15g CO2 per returning visitor

13 resources served from cache · 1 resources re-downloaded

A+
Carbon Budget
10th percentile
PASS
10th percentile
Info::
0.16g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 90% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 10th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.16g

10th percentile

Cleaner than 90% of websites

✓ Below the Web Sustainability Guidelines target

vs Median 74% cleaner ✓
vs Target 69% cleaner ✓
A+
Transfer Efficiency
100% efficient
PASS
100% efficient
Info::
Transfer efficiency: 100%
Only 0 KB of potential savings identified. Your page is well-optimized for size.
100% efficient
Actual transfer 678 KB
Theoretical minimum 678 KB

See Deep Analysis sections above for specific optimizations.

Image Optimization
10 images, 470 KB total, 465 KB wasted
INFO

Image Optimization Audit

Total Images

10

Total Size

470 KB

Oversized

6

Wasted

465 KB

9 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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