Contact

The fastest way to reach us is email:

hello@kdp.cool

We read everything — bug reports, feature requests, calculator suggestions, and corrections to the math or tax data are all welcome. Replies usually within a few days.

Found a bug?

Source code is on GitHub. Open an issue with the page URL, what you entered, what you expected, and what you got. Screenshots help.

Looking for a calculator we don't have?

Email or open a GitHub issue. We prioritize calculators that get high search volume and have authoritative source data we can cite.

What to include

For a calculator bug, include the page URL, the numbers you entered, the filing status or loan term if relevant, and the result you expected. Rounding differences can happen in financial calculators, so exact inputs help us distinguish a real formula issue from display rounding.

For source corrections, include the official table, publication, or reference link. Tax and payroll pages are updated from published source data, not from screenshots or unsourced summaries.

Privacy note

Please do not send tax returns, Social Security numbers, pay stubs, bank statements, loan account numbers, or other sensitive personal documents. Use made-up numbers when possible; we only need enough detail to reproduce the calculator behavior.