The fastest way to reach us is by email: [email protected].
Reporting a calculation issue
Please include:
- the page address (or use the Copy link button under any result — it captures your inputs),
- the result you expected and where it came from,
- your browser and device, if the page did not work as expected.
Suggesting a calculator
Tell us what you are trying to work out and who it is for. Many of our calculators started as reader requests.