Editorial policy

Sources

Every figure on CO2Stats comes from a named source, linked, with the date the source gives itself and the date we checked it. We go to the original where we can reach it: the measuring agency’s data file, the company’s own report, the paper itself, rather than an article about it. Where a figure reached us second-hand, the entry says so.

We quote what a source actually says. A figure given only as “at most” or “over” stays a bound, and a fact the source does not give is shown as “not stated”, never filled in.

Checking

Before a figure is published, it is checked against its source’s own words, and the words are kept beside it: the Kettle ledger carries each claim’s quote, and each host page quotes the company’s evidence. Our own calculations, such as the energy to boil a cup of water, are labelled as ours and show their working.

The CO2 pages and the hosting guide’s grid figures are drawn from published datasets kept with their source, licence and retrieval date. When a dataset is refreshed, the pages say as of when.

Corrections and changes

If you think something here is wrong, write to hello@co2stats.com with what and where. We fix errors promptly. When a figure in the Kettle ledger changes, the old figure stays visible with its date, and the change appears in the ledger’s changelog.

Independence

CO2Stats carries no advertising. Some links to hosting companies may be affiliate links, each marked as such, with a plain explanation above the first one on the page. Whether a host pays us a commission never changes which hosts we list, the order they appear in, or what we say about them.

What we will and will not claim

We follow the UK Competition and Markets Authority’s Green Claims Code. We state specific, measured, dated facts (“this page: 0.12 g CO2e per visit, assessed on 12 October 2026”), never broad claims that a website or a company is “green” or “eco-friendly”. Every carbon figure for a web page is an estimate made with a published method, and says so. A host listed by the Green Web Foundation is described in exactly those terms, with the date we checked.