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https://Zazzle.com

Sustainability

· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
87
GRADE
B
FIX
0
REVIEW
3
PASS
4
INFO
1
Checks
8
4 PASS 3 REVIEW
B
Transfer Efficiency
78% efficient
REVIEW
78% efficient
Info::
Transfer efficiency: 78%
An estimated 292 KB (22%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 292 KB of unused JavaScript. This wasted data produces 0.07g of unnecessary CO2 per page view.
78% efficient

Total waste: 292 KB (22% of page weight)

Unused JS 292 KB

0.07g unnecessary CO2 per visit

Actual transfer 1322 KB
Theoretical minimum 1029 KB
Potential savings 292 KB (0.07g CO2)

See Deep Analysis sections above for specific optimizations.

B
Web Font Weight Variants
No detectable Google Fonts weights
REVIEW
No detectable Google Fonts weights
Info::
No detectable Google Fonts weights
The analyzer detects font weights via Google Fonts URL parameters (~70% of font-using sites). Self-hosted fonts and non-Google CDN fonts aren't visible to URL-based detection. If you self-host fonts, manually audit how many @font-face weights you ship -- 2-3 weights per family is typically enough; 5+ is usually unused payload.
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
0.31g CO2 per view
PASS
0.31g CO2 per view
Info::
0.31g CO2 per page view
This page transfers 1.3 MB, producing an estimated 0.31g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.06g, end-user device 0.23g.
Got: 0.31g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 36.7 kg CO2/year
With 10,000 page views per month, this page would generate approximately 36.7 kg of CO2 annually — equivalent to charging 4583 smartphones.
Info::
Green hosting reduces data center emissions

0.31g

Carbon Footprint per page view

Below sustainability target (0.50g)

Cleaner than 80% of websites

Sustainable Web Design model v4 · Page size: 1.3 MB

Your site
0.31g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.01g
Network
0.06g
End-user device
0.23g
At 10,000 monthly views: Monthly: 3.1 kg · Annual: 36.7 kg · ≈ 4583 smartphone charges
A
Green Hosting
Green (cdn)
PASS
Green (cdn)
Info::
Fastly CDN uses renewable energy
Since most traffic is served through the CDN, the majority of data transfer energy is renewable.
Info::
Fastly: 100% renewable energy for edge network
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 identifiedCDN Fastly

Fastly: 100% renewable energy for edge network

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
96% cached
PASS
96% cached
Info::
96% reduction on repeat visits
Returning visitors download only 57 KB (vs 1322 KB first visit). 77 of 79 resources are served from browser cache, saving 0.29g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.31g)
First visit
1322 KB
Repeat visit
57 KB

96% reduction on repeat visits

Saving 0.29g CO2 per returning visitor

77 resources served from cache · 2 resources re-downloaded

A
Carbon Budget
20th percentile
PASS
20th percentile
Info::
0.31g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 80% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 20th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.31g

20th percentile

Cleaner than 80% of websites

Below the Web Sustainability Guidelines target

vs Median 49% cleaner ✓
vs Target 39% cleaner ✓
Image Optimization
2 images, 0 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

2

Total Size

0 KB

Oversized

2

2 missing dimensions
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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