Editorial policy and corrections

How pages are written

Each calculator page starts from the official rules and figures. We write the explanation, worked example and answers to common questions in plain English, and link every figure to its source. We don’t write about a topic without a primary source to check it against.

Review

Before launch, each section will be reviewed by a named person with relevant experience. Their name and the date of their last review appear on each page. A page whose review is still pending says so.

Use of AI tools

We use AI tools to help draft code and copy. A person checks every figure against its source and every calculation against tests before it goes live, and is responsible for what we publish.

Independence

Advertisers and partners have no say over what we write or how a calculator works.

Corrections

If you spot a mistake, please tell us. We aim to fix confirmed errors within two working days and list them here.