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Why Chalk Calculator
It shows its work
Every calculator states its formula, its assumptions and what it cannot tell you. Where a figure comes from a published source, that source is linked.
Nothing you type is stored
Calculations run in your browser. No salary, loan balance or debt figure is sent to a server, written to a URL or saved anywhere.
It says when it does not know
Where a result depends on something we cannot model reliably — a state’s tax brackets, an aggregate’s density — the calculator says so rather than guessing.