Contact Us
Found a mistake, need a calculator we do not have, or want to ask something? Here is how to reach us.
Email us
The quickest way to reach us is by email:
We read every message and aim to reply within two to three working days. There is no contact form on this page on purpose — a form would mean collecting and storing your details on a server, and we would rather not hold data we do not need.
What to include
Reporting a calculation problem
This is the most useful kind of message we get, and the easiest to act on if you include three things:
- Which calculator and which tab you were using.
- The exact numbers you entered.
- The answer you expected, and the answer you saw.
Even quicker: press Copy link under any result and paste that link into your email. It reproduces your exact calculation at our end.
Suggesting a calculator
Tell us the question you are trying to answer and the situation it comes up in. Real use cases shape better tools than feature names do.
Reporting a broken page
Let us know the page address, the device and browser you were using, and what went wrong. A screenshot helps.
Advertising and business enquiries
Use the same address with "Advertising" in the subject line.
Before you write
Many questions are already answered on the calculator pages themselves, each of which has a frequently asked questions section covering the formula, the edge cases and the usual mistakes. The homepage guide covers percentage basics in more depth.