https://schalke04.de
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
81
GRADE
B
FIX
1
REVIEW
3
PASS
3
INFO
1
Checks
83 PASS 3 REVIEW 1 FIX
DCarbon BudgetAction55th percentileFIX
Carbon Budget
Action55th percentile
55th percentile
Warning::
0.79g CO2 — above the median website (0.60g)
Heavier than an estimated 45% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 55th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
0.79g
55th percentile
Cleaner than 45% of websites
✗ Above the median website
vs Median 32% more
vs Target 59% more
BCO2 Per Page Load0.79g CO2 per viewREVIEW
CO2 Per Page Load
0.79g CO2 per view
0.79g CO2 per view
Info::
0.79g CO2 per page view
This page transfers 3.4 MB, producing an estimated 0.79g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.16g, end-user device 0.61g.
Got: 0.79g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 95.3 kg CO2/year
With 10,000 page views per month, this page would generate approximately 95.3 kg of CO2 annually — equivalent to charging 11917 smartphones.
Info::
Green hosting reduces data center emissions
0.79g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 45% of websites
Sustainable Web Design model v4 · Page size: 3.4 MB
Your site
0.79g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.02g
Network
0.16g
End-user device
0.61g
At 10,000 monthly views: Monthly: 7.9 kg · Annual: 95.3 kg · ≈ 11917 smartphone charges
BTransfer Efficiency84% efficientREVIEW
Transfer Efficiency
84% efficient
84% efficient
Info::
Transfer efficiency: 84%
An estimated 550 KB (16%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 550 KB of unused JavaScript. This wasted data produces 0.13g of unnecessary CO2 per page view.
Total waste: 550 KB (16% of page weight)
Unused JS 550 KB
0.13g unnecessary CO2 per visit
Actual transfer 3437 KB
Theoretical minimum 2886 KB
Potential savings 550 KB (0.13g 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.
A+Green HostingGreen (both)PASS
Green Hosting
Green (both)
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Google Cloud, CDN: Cloudflare
Info::
Google Cloud: Verified by the Green Web Foundation
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 Google Cloud✓CDN Cloudflare✓
Google Cloud: Verified by the Green Web Foundation
Cloudflare: 100% renewable energy for global network since 2019
Based on known provider commitments. Verify at thegreenwebfoundation.org
A+Repeat Visit Weight99% cachedPASS
Repeat Visit Weight
99% cached
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 30 KB (vs 3437 KB first visit). 190 of 199 resources are served from browser cache, saving 0.79g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.79g)
First visit
3437 KB
Repeat visit
30 KB
99% reduction on repeat visits
Saving 0.79g CO2 per returning visitor
190 resources served from cache · 9 resources re-downloaded
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: Cloudflare
Image Optimization66 images, 171 KB total, 45 KB wastedINFO
Image Optimization
66 images, 171 KB total, 45 KB wasted
Image Optimization Audit
Total Images
66
Total Size
171 KB
Oversized
5
Wasted
45 KB
64 missing dimensions 56 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.