DimeCalc is a set of free personal-finance calculators that run entirely in your browser.
Most calculator sites route what you type — your salary, debts, rent — through their servers and then monetize it. DimeCalc is a static site: the math happens locally in your tab. Turn off your internet after the page loads and every calculator keeps working. Nothing you enter is uploaded, stored, or tracked.
No sign-up, no accounts, no paywall, and no ads. Completely free.