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Calculators

The math, computed. Never hallucinated.

The lessons teach you to set up the math and hand it off, because a language model computing a payment or an IRR is a wrong number with a confident face. These calculators are the other half: real, deterministic math in your browser — no AI in the loop — so the number is right and the assumptions are on the table.

Every calculator is a planning estimate from your inputs, computed here, not by an AI. None is a valuation, an appraisal, or tax, legal, or investment advice. Confirm figures with your own model and the right professional before you rely on them.