What you'll find here
- Basic Calculator — a full calculator with keyboard support, right on the homepage.
- BMI Calculator — body mass index with healthy weight range, metric or imperial.
- Percentage Calculator — three percentage tools side by side.
- Loan Calculator — payments, total interest and a year-by-year balance table.
- Compound Interest — savings growth with monthly contributions.
- Age Calculator — exact age and next-birthday countdown.
- Tip Calculator — tip and bill splitting that updates as you type.
- Unit Converter — length, weight, temperature and volume.
Private by design
Every calculation happens in your own browser. Nothing you type is sent to a server, stored, or shared — close the tab and it's gone. The math uses standard published formulas, noted at the bottom of each calculator page.
Why we built CalculatorWorks
Everybody hits the same few number questions over and over. What's the tip on $86? What would the monthly payment be on that car? Search for any of these and you usually land on a page that makes you close two pop-ups before you can even see the calculator. We got tired of that, so we built this. Each tool loads fast, gives you the answer, and doesn't ask for your email.
Under every tool there's a short explanation of the formula and a worked example, in case you want to know why the number is what it is. That part's optional. The calculator works fine without reading a word of it.
How we keep the numbers right
Each tool uses the standard published formula for its job: the WHO categories for BMI, the amortization formula for loans, monthly compounding for savings. The formula is printed on each page so you can check the working yourself. Where an answer depends on custom or judgment, like tipping norms or future investment returns, the page says so instead of pretending the number is gospel.
Get in touch
Spotted a mistake, or want a calculator we don't have? Email petshoppawsandwhiskers@gmail.com. We read everything, and reader suggestions decide what gets built next.