https://bzh-freiburg.de
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
90
GRADE
A
FIX
0
REVIEW
2
PASS
5
INFO
1
Checks
85 PASS 2 REVIEW
BGreen HostingGreen (hosting)REVIEW
Green Hosting
Green (hosting)
Green (hosting)
Info::
Hetzner uses renewable energy
Info::
Hetzner: Verified by the Green Web Foundation
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 Hetzner✓CDN Not identified✗
Hetzner: Verified by the Green Web Foundation
Based on known provider commitments. Verify at thegreenwebfoundation.org
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.
ACO2 Per Page Load0.21g CO2 per viewPASS
CO2 Per Page Load
0.21g CO2 per view
0.21g CO2 per view
Info::
0.21g CO2 per page view
This page transfers 0.9 MB, producing an estimated 0.21g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.01g, network 0.04g, end-user device 0.16g.
Got: 0.21g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 25.4 kg CO2/year
With 10,000 page views per month, this page would generate approximately 25.4 kg of CO2 annually — equivalent to charging 3169 smartphones.
Info::
Green hosting reduces data center emissions
0.21g
Carbon Footprint per page view
✓ Below sustainability target (0.50g)
Cleaner than 89% of websites
Sustainable Web Design model v4 · Page size: 0.9 MB
Your site
0.21g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.01g
Network
0.04g
End-user device
0.16g
At 10,000 monthly views: Monthly: 2.1 kg · Annual: 25.4 kg · ≈ 3169 smartphone charges
A+Repeat Visit Weight95% cachedPASS
Repeat Visit Weight
95% cached
95% cached
Info::
95% reduction on repeat visits
Returning visitors download only 46 KB (vs 914 KB first visit). 26 of 28 resources are served from browser cache, saving 0.20g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.21g)
First visit
914 KB
Repeat visit
46 KB
95% reduction on repeat visits
Saving 0.20g CO2 per returning visitor
26 resources served from cache · 2 resources re-downloaded
ACarbon Budget11th percentilePASS
Carbon Budget
11th percentile
11th percentile
Info::
0.21g CO2 — below the sustainability target of 0.50g
Cleaner than an estimated 89% of websites analyzed. This page meets the Web Sustainability Guidelines target.
Info::
Estimated 11th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.21g
11th percentile
Cleaner than 89% of websites
✓ Below the Web Sustainability Guidelines target
vs Median 65% cleaner ✓
vs Target 58% cleaner ✓
A+Transfer Efficiency95% efficientPASS
Transfer Efficiency
95% efficient
95% efficient
Info::
Transfer efficiency: 95%
Only 49 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 49 KB (5% of page weight)
Unused JS 49 KB
0.01g unnecessary CO2 per visit
Actual transfer 914 KB
Theoretical minimum 864 KB
Potential savings 49 KB (0.01g CO2)
See Deep Analysis sections above for specific optimizations.
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Hetzner Online GmbH
Image Optimization14 images, 508 KB total, 0 KB wastedINFO
Image Optimization
14 images, 508 KB total, 0 KB wasted
Image Optimization Audit
Total Images
14
Total Size
508 KB
Oversized
1
7 missing alt text 6 missing dimensions 6 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.