CalcSite

Calculators that show their working. Each one shows the formula it uses, works through real examples, and says what happens at the edges.

Finance calculators

  • Compound Interest Calculator

    Work out what a lump sum plus regular deposits grows to at monthly, quarterly or daily compounding — and see how much of the final balance is interest.

  • Credit Card Minimum Payment Calculator

    See how long a credit card balance takes to clear if you only ever pay the minimum — and why the minimum shrinks as the balance falls. Includes the case where it never clears at all.

  • Debt Payoff Calculator

    Work out how many months a fixed monthly payment needs to clear a balance, how much interest it costs, and the payment below which the debt never clears at all.

  • Mortgage Extra Payments Calculator

    See what an extra monthly payment, an annual lump sum, or both do to a mortgage: how many years come off the term and how much interest disappears.

  • Mortgage Calculator

    Work out the monthly payment on a home loan, and see what the loan costs in total once interest is included. Compare terms side by side before you commit.

  • Savings Goal Calculator

    Work backwards from a target: enter what you want to end up with and see the monthly deposit it takes, including the interest those deposits earn along the way.

  • Simple Interest Calculator

    Work out simple interest, where the interest never earns interest of its own. Shows the yearly breakdown and compares the result against compounding.