BMI Calculator
Estimate body mass index from height and weight.
Calculators
BMI
Body mass index and category.
Mortgage
Monthly payment and total interest.
Compound Interest
Growth from principal, rate, time, and compounding.
Tip Splitter
Tip, total, and per-person amount.
Percentage
Find percent of a number.
Discount
Sale price and amount saved.
Loan
Installment payment for fixed-rate loans.
Fuel Cost
Trip fuel use and cost estimate.
How to Use Online Calculators Responsibly
Calculators are useful for estimates, but the assumptions matter. A mortgage calculator does not include every tax or insurance charge unless you enter those values separately. A BMI calculator is a broad screening measure, not a diagnosis. A fuel-cost calculator depends on traffic, driving style, vehicle load, and local prices.
Common Formula Reference
| Calculator | Formula used |
|---|---|
| Percentage | result = value x percent / 100 |
| Discount | final price = original price - original price x discount / 100 |
| BMI | BMI = weight kg / height m squared |
| Compound interest | A = P(1 + r/n)^(nt) |
| Fuel cost | cost = distance / 100 x efficiency x fuel price |
When to Double-Check
Double-check results before making medical, financial, legal, or safety decisions. Use the calculator output as a starting estimate and confirm important numbers with a qualified professional or the official provider.