Write to us
Email [email protected], or pick the reason below to start a message with the subject filled in.
- Report a calculation error →A result looks wrong, or a formula needs a better reference. Include the calculator, your inputs, and what you expected.
- Suggest a tool →A calculator, converter, or quality tool you would use. Say what it should compute and which standard or method it follows.
- Anything else →Embedding the calculators, custom calculators for your own methods, or general questions.
For calculation issues, a screenshot or the image from the calculator's Save image button is the quickest way to show exactly what you entered.
Custom calculators
If you need a calculator built around your own method, units, or reporting format, describe what it should compute and how you use the result — custom work is considered case by case.