Contact

Found a bug in a formula? A widget that won't load? Want a calculator we don't have yet? We'd like to know.

Email

We read everything. We don't reply to everything — but we read everything.

Reporting a calculation error

Please include the URL of the calculator, the inputs you used, the result you got, and the result you expected. The more specific, the faster we fix it.

Suggesting a new calculator

Tell us what you'd type in and what you'd want out. Bonus points if you can point at a paper, textbook chapter, or industry standard with the formula.