This page explains how tools and guides on Free Online Tools are built, checked and corrected.
How a tool is built
- Method first. Each tool starts from a published formula, rule or standard, such as the IELTS rounding rule or the NHS BMI categories.
- Tested against worked examples. Results are checked against examples from the source, and against edge cases such as zero values, very large numbers and boundary dates.
- Checked on phones and desktops before it’s published.
Sources
Tools that depend on rules cite the official source on the page: government sites, regulators, testing bodies or health services. Third-party summaries aren’t used as the main source.
Keeping tools current
Pages show when they were last updated. Tools based on rules that change on fixed dates, such as tax years, are reviewed before each change takes effect.
Corrections
If a mistake is reported through the contact page, it’s checked against the source and fixed as soon as possible, and the page’s “last updated” date changes.
AI and automation
AI tools may help draft code and text. Every tool is tested and every page is reviewed against its sources before publication.
Advertising and independence
The site is funded by advertising. Advertisers have no say in tool results or guide content, and there are no paid placements.