Get in touch
Spotted a wrong number, want a new tool, or just have feedback? We read every message, and calculation errors get fixed first.
A wrong number is the most serious thing that can go wrong here, so error reports jump the queue. To let us reproduce it in one go, please include:
- the page address (or use the tool's Share button — the link carries your inputs)
- the numbers you entered and the figure the tool returned
- the figure you expected, and where it came from
We check every reported formula against its cited source. Where a tool is wrong we fix it and move its last-updated date; where it is right but unclear we rewrite the explanation.
What happens after you write
We read everything that arrives, and we answer from one address rather than a ticket system. Expect a reply within two to three working days; a reported calculation error usually gets one sooner, because that is the message we act on first.
If a figure is wrong we correct the tool, re-run the check that recomputes every worked example on the site, and move the page’s last-updated date so you can see it changed. If the figure turns out to be right but the page explained it badly, we rewrite the explanation instead — and we will tell you which of the two happened. We do not quietly close reports.
What we cannot help with
We cannot tell you what to do with your money, your health or your building. Every calculator here states the formula it uses and the source it came from, and that is genuinely the limit of what we can stand behind — a question that needs someone to look at your circumstances needs a qualified adviser, a GP or a chartered engineer, not us. We also cannot recover a calculation you made: the tools run in your browser and the numbers never reach us.