Contact

What's worth emailing about

Bugs. If a tool produces a wrong answer or behaves unexpectedly, please include the inputs you used and what you expected to happen.
Feature requests. A new tool you'd like to see, or an enhancement to an existing one. Concrete use cases help.
Accuracy or formula questions. If a calculator's math doesn't match a reference the reference along. We'll either fix the tool or document the difference.
Accessibility issues. Mobile, screen reader, keyboard navigation.
Privacy concerns. If something on the site looks like it could be leaking data, we want to hear about it. See the privacy page for the full commitment.

Promotional outreach. Link-building, guest-post pitches, "we noticed your site..." : please don't. They are deleted unread.
"Is my data safe?" questions. Yes. Read the privacy page and inspect the network tab in your browser to verify. We can't tell you anything you can't verify yourself.

We read everything but reply only when something can be acted on or clarified. Bug reports usually get a response within a few days.