Write to hello@example.com. We read every message, although we cannot always reply individually.
Reporting a problem
To help us reproduce the issue quickly, please include:
- the name or address of the calculator or tool;
- the exact values or options you used — for file tools, the file type and size and what happened;
- the result you saw and the result you expected, with your reasoning or source if possible;
- your browser and device.
Only include what is needed to show the problem. Please don’t send sensitive personal, health or financial details, and don’t attach confidential files — a small sample that shows the issue is ideal.
Suggesting something new
Tell us what you are trying to work out or do, and any formula, standard or file format it should follow.
What we can’t help with
We can’t give personal financial, tax, legal or medical advice, or recover files. For decisions in those areas, please consult a qualified professional.