Skip to content
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
8
3 PASS 3 REVIEW 1 FIX
D
Carbon Budget
Action
55th percentile
FIX
55th percentile
Warning::
0.78g 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

0.78g

55th percentile

Cleaner than 45% of websites

Above the median website

vs Median 30% more
vs Target 56% more
B
CO2 Per Page Load
0.78g CO2 per view
REVIEW
0.78g CO2 per view
Info::
0.78g CO2 per page view
This page transfers 3.3 MB, producing an estimated 0.78g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.16g, end-user device 0.60g.
Got: 0.78g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 93.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 93.5 kg of CO2 annually — equivalent to charging 11689 smartphones.
Info::
Green hosting reduces data center emissions

0.78g

Carbon Footprint per page view

Above sustainability target (0.50g)

Cleaner than 45% of websites

Sustainable Web Design model v4 · Page size: 3.3 MB

Your site
0.78g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.16g
End-user device
0.60g
At 10,000 monthly views: Monthly: 7.8 kg · Annual: 93.5 kg · ≈ 11689 smartphone charges
B
Transfer Efficiency
84% efficient
REVIEW
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.
84% efficient

Total waste: 550 KB (16% of page weight)

Unused JS 550 KB

0.13g unnecessary CO2 per visit

Actual transfer 3371 KB
Theoretical minimum 2820 KB
Potential savings 550 KB (0.13g 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.
A+
Green Hosting
Green (both)
PASS
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 CloudCDN 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 Weight
99% cached
PASS
99% cached
Info::
99% reduction on repeat visits
Returning visitors download only 30 KB (vs 3371 KB first visit). 184 of 192 resources are served from browser cache, saving 0.77g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.78g)
First visit
3371 KB
Repeat visit
30 KB

99% reduction on repeat visits

Saving 0.77g CO2 per returning visitor

184 resources served from cache · 8 resources re-downloaded

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Image Optimization
66 images, 171 KB total, 45 KB wasted
INFO

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.

Send Feedback