18 purpose-built calculators for money, health, home and everyday math
A general-purpose calculator makes you remember the formula; a purpose-built one just asks for the inputs you already know. That's the idea behind this category: each calculator handles one real-life computation — a restaurant tip, a mortgage payment, a body-mass index, a semester GPA — with the formula, units and edge cases built in.
Every calculator computes instantly in your browser as you type. None of your numbers — not your salary, weight, due date or loan amount — are sent anywhere, which makes these tools appropriate for genuinely personal math. They're free, unlimited and work identically on desktop and mobile.
Estimate how many liters or gallons of paint a room needs from wall dimensions and coats. Open the Paint →
How to Choose the Right Tool
For money questions, reach for the Percentage, Discount, Sales Tax, Tip or Split Bill calculators for quick arithmetic, and Mortgage or Compound Interest for longer horizons. Health and body calculators — BMI, Body Fat, Calorie, Pregnancy and Ovulation — estimate widely used medical formulas (always as guidance, not diagnosis). The Hours Calculator and GPA Calculator handle work and school bookkeeping, while Carpet and Paint calculators translate room dimensions into shopping quantities. The Scientific Calculator covers everything with trigonometry, logs and powers, and Fuel Cost estimates what a trip will really cost.
Frequently Asked Questions
Are the health calculators medically reliable?
They use standard published formulas (like BMI and the Mifflin-St Jeor equation) that are useful for orientation, but they're not a substitute for professional medical advice.
Are my numbers stored or transmitted?
No. Every calculation runs locally in your browser — nothing you enter is uploaded or logged.
Do the financial calculators account for taxes and fees?
They compute the standard formulas (amortization, compound interest, percentages). Local taxes or bank fees vary, so treat results as close estimates.
Can I use these calculators on mobile?
Yes — all calculators are responsive and designed for quick one-handed use on phones.
Explore More WiserWork Categories
WiserWork offers 295 free browser-based tools across 22 categories — all private, all free, no sign-up required.