Financial calculators

Know the number before you decide

Free tools for the arithmetic behind a mortgage, a lease and a pile of savings. Every formula is written out, every assumption belongs to you, and no page tells you what to do with the result.

Browse the calculators

Every figure shows its work

  • The formula sits next to the answer, in plain language and in symbols.
  • Every number that comes from somewhere carries its source and its date.
  • Every tool states what it does not do, in the same words, right under the result.

How the site is built →

Monthly payment

$2,358.42

Principal & interest

$1,984.12

Property tax

$280.00

Total interest

$446,031

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One short letter when a new calculator goes live or an existing one is re-reviewed. No offers, no sponsored placements.