Contact

Message me directly if you spot an error, if a result looks wrong, or if you want to propose a feature. You will get a human reply, not an auto-responder.

How to reach me

If you send a bug, include the exact values you entered and what you expected. That helps me reproduce it fast.

When I reply

Usually within 24–48 hours, evenings or weekends. If it is urgent, add “URGENT” to the subject.

What I do not do

I do not collect personal data and I do not sell ads in shady bundles. My priority is to keep the formulas correct and useful.

Thank you for the feedback

Every message helps me improve the site. If I reply late, nudge me—I am human, not a robot.