Glossary
Plain-English definitions of the terms behind the calculators. Each entry links back to the relevant tools so you can see the math in action.
Finance
Amortization
The schedule by which an installment loan's balance is paid down over time.
APR (Annual Percentage Rate)
The yearly cost of a loan, expressed as a percentage that includes interest plus mandatory fees.
Compound Interest
Interest earned on the original principal plus all previously-accumulated interest.
Debt-to-Income Ratio (DTI)
The share of your gross monthly income that goes to debt payments.
Internal Rate of Return (IRR)
The annualized rate at which a series of cash flows breaks even — the discount rate that makes net present value zero.
PITI
Principal, Interest, Taxes, Insurance — the four components of a mortgage payment.
Tax
Health
Basal Metabolic Rate (BMR)
Calories your body burns at complete rest just to keep its systems running.
Body Mass Index (BMI)
Weight (kg) divided by height squared (m²). A coarse population-level screening number.
Total Daily Energy Expenditure (TDEE)
The total calories you burn in a typical day — basal metabolism plus activity.
Math & Stats
Developer & Web
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