5,819+ calculators for finance, health, construction and more

Free online loan calculator: monthly payment, total interest and total cost for any amount, rate and term. Choose equal (annuity) or declining (differentiated) payments. No signup, instant results.

Free mortgage calculator: monthly payment, total interest and total cost from the loan amount, rate and term. Compare 15-year vs 30-year terms and equal vs declining payments.

Free BMI calculator: enter your height in cm and weight in kg to get your Body Mass Index and its WHO category — underweight, normal weight, overweight or obesity class I–III.

Calculate the future value of your investments with compound interest: starting amount, monthly contributions, annual rate and term. Interest compounds monthly; see total contributed, earnings and annual return.

Calculate sales tax with presets for California 7.25%, New York 4% (NYC 8.875%), Texas 6.25%, Florida 6% and UK VAT 20%, or enter any rate. Add tax to a price or extract it from a total.

Calculate Area of a Square instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Area of a Rectangle instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Triangle Area (base × height) instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Triangle Area (Heron's formula) instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Triangle Area (two sides & angle) instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Equilateral triangle area instantly with the exact formula and a worked example.

Calculate Isosceles triangle area instantly with the exact formula and a worked example.

Calculate Area of a Parallelogram instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Area of a Rhombus instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.

Calculate Area of a Trapezoid instantly. Free online calculator with the exact formula, a worked example, and metric units. No signup required.