https://hannahseo.com
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
Checks
84 PASS 3 REVIEW
BTransfer Efficiency90% efficientREVIEW
Transfer Efficiency
90% efficient
90% efficient
Info::
Transfer efficiency: 90%
An estimated 64 KB (10%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 64 KB of unused JavaScript. This wasted data produces 0.01g of unnecessary CO2 per page view.
Total waste: 64 KB (10% of page weight)
Unused JS 64 KB
0.01g unnecessary CO2 per visit
Actual transfer 616 KB
Theoretical minimum 551 KB
Potential savings 64 KB (0.01g CO2)
See Deep Analysis sections above for specific optimizations.
BWeb Font Weight VariantsNo detectable Google Fonts weightsREVIEW
Web Font Weight Variants
No detectable Google Fonts weights
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.
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
A+CO2 Per Page Load0.14g CO2 per viewPASS
CO2 Per Page Load
0.14g CO2 per view
0.14g CO2 per view
Info::
0.14g CO2 per page view
This page transfers 0.6 MB, producing an estimated 0.14g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.00g, network 0.03g, end-user device 0.11g.
Got: 0.14g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 17.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 17.1 kg of CO2 annually — equivalent to charging 2137 smartphones.
Info::
Green hosting reduces data center emissions
0.14g
Carbon Footprint per page view
✓ Below sustainability target (0.50g)
Cleaner than 90% of websites
Sustainable Web Design model v4 · Page size: 0.6 MB
Your site
0.14g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.00g
Network
0.03g
End-user device
0.11g
At 10,000 monthly views: Monthly: 1.4 kg · Annual: 17.1 kg · ≈ 2137 smartphone charges
AGreen HostingGreen (cdn)PASS
Green Hosting
Green (cdn)
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 Weight100% cachedPASS
Repeat Visit Weight
100% cached
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 2 KB (vs 616 KB first visit). 7 of 8 resources are served from browser cache, saving 0.14g CO2 per repeat visit.
Info::
Repeat visit: 0.00g CO2 (first visit: 0.14g)
First visit
616 KB
Repeat visit
2 KB
100% reduction on repeat visits
Saving 0.14g CO2 per returning visitor
7 resources served from cache · 1 resources re-downloaded
A+Carbon Budget10th percentilePASS
Carbon Budget
10th percentile
10th percentile
Info::
0.14g 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
0.14g
10th percentile
Cleaner than 90% of websites
✓ Below the Web Sustainability Guidelines target
vs Median 76% cleaner ✓
vs Target 72% cleaner ✓
Image Optimization1 images, 311 KB total, 266 KB wastedINFO
Image Optimization
1 images, 311 KB total, 266 KB wasted
Image Optimization Audit
Total Images
1
Total Size
311 KB
Oversized
1
Wasted
266 KB
1 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.