About CalcKit

Useful numbers, without the extra steps.

CalcKit brings together free calculators for business, finance, freelance work and everyday life. No account is required. Each tool shows its formula, a worked example and the assumptions behind the result.

How results are calculated

Calculations run in your browser using standard mathematical formulas. Inputs are checked before calculation. We keep full precision during the calculation and round only the displayed result, so totals from individually rounded numbers can differ slightly.

Currency and dates

Money is displayed in US dollars. You can enter another currency when every monetary input uses that same unit; no exchange-rate conversion is performed. Dates are calendar dates rather than timestamps. The date tools explain their leap-year and inclusive-counting conventions.

Financial estimates

Finance tools use simplified models. Interest rates remain constant, contributions follow the stated schedule, and fees, taxes and inflation are excluded unless a tool explicitly says otherwise. Results are general information and mathematical estimates, not financial or investment advice.

Free and focused

There are no ads or affiliate placements in this version. Any future sponsored content will be labeled and will not affect formulas or results.