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https://Hammer3.com

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
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
0.16g 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: 19.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 19.3 kg of CO2 annually — equivalent to charging 2413 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: 19.3 kg · ≈ 2413 smartphone charges
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 identifiedCDN Cloudflare

Cloudflare: 100% renewable energy for global network since 2019

Based on known provider commitments. Verify at thegreenwebfoundation.org

A+
Repeat Visit Weight
100% cached
PASS
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 1 KB (vs 696 KB first visit). 21 of 22 resources are served from browser cache, saving 0.16g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.16g)
First visit
696 KB
Repeat visit
1 KB

100% reduction on repeat visits

Saving 0.16g CO2 per returning visitor

21 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 73% cleaner ✓
vs Target 68% cleaner ✓
A+
Transfer Efficiency
94% efficient
PASS
94% efficient
Info::
Transfer efficiency: 94%
Only 41 KB of potential savings identified. Your page is well-optimized for size.
94% efficient

Total waste: 41 KB (6% of page weight)

Unused JS 41 KB

0.01g unnecessary CO2 per visit

Actual transfer 696 KB
Theoretical minimum 654 KB
Potential savings 41 KB (0.01g CO2)

See Deep Analysis sections above for specific optimizations.

Image Optimization
8 images, 240 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

8

Total Size

240 KB

Oversized

1

3 missing alt text 4 missing dimensions 3 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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