Climate tech · rank 22 of 113
Persefoni's website emits 1.03 g of CO2 per visit, 2.9× the worst passing grade.
That is 0.75 g below the cohort median of 1.78 g, and puts the site in the lightest 25% of the 113 companies ranked this edition.
Grade F on the Sustainable Web Design scale. How grades A+ to F are set.
The numbers behind it
Annual figures cover the 30 pages I measured and estimated organic search traffic only, so the real total is higher. Coverage is published so you can judge how representative the number is.
One visit ≈ a 10-watt LED bulb for 12 minutes. A year of estimated search visits to the pages measured ≈ driving a new car 1,000 km. What these numbers mean
Where this site sits in the cohort
Grades A+ to E: up to 0.36 g. 2 companies here.
- A+up to 0.040 g0 companies
- Aup to 0.079 g0 companies
- Bup to 0.145 g1 company
- Cup to 0.209 g0 companies
- Dup to 0.278 g1 company
- Eup to 0.359 g0 companies
- Fabove 0.359 g111 companies
Persefoni is the dark bar. The band along the bottom is every passing grade, A+ to E.
Against the other climate tech companies
Bars share one scale within the sector, lightest first. Climate tech companies I couldn't measure fairly are listed on the withheld page. See all climate tech companies.
Why this company is in the index
Listed because: Carbon accounting SaaS.
Claims: Cleantech
Inclusion is based on a company's own public claims, never on whether it is a client of mine. How this is measured.
Work at Persefoni? I can show you which pages carry the weight and what it would take to cut it.
Cite this: The Green Blind Spot, 2026-Q4 edition, Baba SEO. https://greenblindspot.com/2026-q4/company/persefoni-com/