https://developer.apple.com
Sustainability
· 8 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.SCORE
66
GRADE
D
FIX
3
REVIEW
2
PASS
2
INFO
1
Checks
82 PASS 2 REVIEW 3 FIX
FCO2 Per Page LoadAction2.23g CO2 per viewFIX
CO2 Per Page Load
Action2.23g CO2 per view
2.23g CO2 per view
Critical::
2.23g CO2 per page view
This page transfers 7.9 MB, producing an estimated 2.23g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.41g, network 0.39g, end-user device 1.43g.
Got: 2.23g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 268.1 kg CO2/year
With 10,000 page views per month, this page would generate approximately 268.1 kg of CO2 annually — equivalent to charging 33515 smartphones.
2.23g
Carbon Footprint per page view
✗ Above sustainability target (0.50g)
Cleaner than 5% of websites
Sustainable Web Design model v4 · Page size: 7.9 MB
Your site
2.23g
Top 10%
0.20g
Target
0.50g
Median website
0.60g
Energy Breakdown
Data center
0.41g
Network
0.39g
End-user device
1.43g
At 10,000 monthly views: Monthly: 22.3 kg · Annual: 268.1 kg · ≈ 33515 smartphone charges
DGreen HostingActionUnknownFIX
Green Hosting
ActionUnknown
Unknown
Info::
Hosting provider could not be identified
Without knowing the provider, we cannot determine their energy sourcing. Check with your hosting provider about their renewable energy commitments.
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 HostingUnable to Determine
Hosting Not identified✗CDN Not identified✗
Based on known provider commitments. Verify at thegreenwebfoundation.org
FCarbon BudgetAction95th percentileFIX
Carbon Budget
Action95th percentile
95th percentile
Warning::
2.23g CO2 — above the median website (0.60g)
Heavier than an estimated 5% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 95th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website
2.23g
95th percentile
Cleaner than 5% of websites
✗ Above the median website
vs Median 272% more
vs Target 347% more
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+Repeat Visit Weight100% cachedPASS
Repeat Visit Weight
100% cached
100% cached
Info::
100% reduction on repeat visits
Returning visitors download only 21 KB (vs 8079 KB first visit). 77 of 78 resources are served from browser cache, saving 2.23g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 2.23g)
First visit
8079 KB
Repeat visit
21 KB
100% reduction on repeat visits
Saving 2.23g CO2 per returning visitor
77 resources served from cache · 1 resources re-downloaded
A+Transfer Efficiency100% efficientPASS
Transfer Efficiency
100% efficient
100% efficient
Info::
Transfer efficiency: 100%
Only 21 KB of potential savings identified. Your page is well-optimized for size.
Total waste: 21 KB (0% of page weight)
Unused JS 21 KB
0.01g unnecessary CO2 per visit
Actual transfer 8079 KB
Theoretical minimum 8057 KB
Potential savings 21 KB (0.01g CO2)
See Deep Analysis sections above for specific optimizations.
Image Optimization33 images, 6275 KB total, 3369 KB wastedINFO
Image Optimization
33 images, 6275 KB total, 3369 KB wasted
Image Optimization Audit
Total Images
33
Total Size
6275 KB
Oversized
24
Wasted
3369 KB
29 missing dimensions 20 missing lazy loading
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.