Skip to content
https://ulule.com

Sustainability

· 6 checks — CO2 emissions, green hosting, repeat-visit weight, carbon budget, and transfer efficiency rolled into one auditable list.
SCORE
76
GRADE
C
FIX
2
REVIEW
1
PASS
3
INFO
0
Device:
Mobile Desktop
Checks
6
3 PASS 1 REVIEW 2 FIX
D
CO2 Per Page Load
Action
0.81g CO2 per view
FIX
0.81g CO2 per view
Info::
0.81g CO2 per page view
This page transfers 3.4 MB, producing an estimated 0.81g of CO2 per visit using the Sustainable Web Design model (v4). Breakdown: data center 0.02g, network 0.17g, end-user device 0.62g.
Got: 0.81g CO2 Expected: < 0.50g (sustainability target)
Info::
At 10,000 monthly views: 97.5 kg CO2/year
With 10,000 page views per month, this page would generate approximately 97.5 kg of CO2 annually — equivalent to charging 12182 smartphones.
Info::
Green hosting reduces data center emissions

0.81g

Carbon Footprint per page view

✗ Above sustainability target (0.50g)

Cleaner than 44% of websites

Sustainable Web Design model v4 · Page size: 3.4 MB

Your site
0.81g
Top 10%
0.20g
Target
0.50g
Median website
0.60g

Energy Breakdown

Data center
0.02g
Network
0.17g
End-user device
0.62g
At 10,000 monthly views: Monthly: 8.1 kg · Annual: 97.5 kg · ≈ 12182 smartphone charges
D
Carbon Budget
Action
56th percentile
FIX
56th percentile
Warning::
0.81g CO2 — above the median website (0.60g)
Heavier than an estimated 44% of websites. Reducing page weight, optimizing images, and removing unused JavaScript would lower the carbon footprint. See the Performance tab.
Info::
Estimated 56th percentile
Compared to: top 10% = 0.20g, target = 0.50g, median = 0.60g per page view.
Top 10%
Target
Median website

0.81g

56th percentile

Cleaner than 44% of websites

✗ Above the median website

vs Median 35% more
vs Target 62% more
B
Transfer Efficiency
86% efficient
REVIEW
86% efficient
Info::
Transfer efficiency: 86%
An estimated 489 KB (14%) could be eliminated: 0 KB via better compression, 0 KB via modern image formats, 489 KB of unused JavaScript. This wasted data produces 0.11g of unnecessary CO2 per page view.
86% efficient

Total waste: 489 KB (14% of page weight)

Unused JS 489 KB

0.11g unnecessary CO2 per visit

Actual transfer 3513 KB
Theoretical minimum 3024 KB
Potential savings 489 KB (0.11g CO2)

See Deep Analysis sections above for specific optimizations.

A+
Green Hosting
Green (both)
PASS
Green (both)
Info::
Both hosting and CDN use renewable energy
Got: Hosting: Amazon Web Services, CDN: Cloudflare
Info::
Amazon Web Services: 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 Amazon Web Services✓CDN Cloudflare✓

Amazon Web Services: 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 40 KB (vs 3513 KB first visit). 96 of 101 resources are served from browser cache, saving 0.80g CO2 per repeat visit.
Info::
Repeat visit: 0.01g CO2 (first visit: 0.81g)
First visit
3513 KB
Repeat visit
40 KB

99% reduction on repeat visits

Saving 0.80g CO2 per returning visitor

96 resources served from cache · 5 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

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback