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Down Payment Planner

How long until I can afford a home?

The model behind this calculator

spec v1.0.0 · 250 open cases

This calculator runs a published model: its inputs, formulas, assumptions, and exclusions are documented in a versioned specification, and it is Concordance-tested — an independent second implementation, built from that spec alone, must agree with it on 250 open test cases before any change ships. The same model is callable by AI assistants and developers.