About Advanced Calculator

Why this site exists

Most calculator sites answer a simple question surrounded by pop-ups, cookie walls and six paragraphs of filler before the actual tool. Advanced Calculator is the opposite arrangement: the calculator is the first thing on the page, it works immediately, and the explanation underneath is there if you want it.

Every tool here is one we reached for ourselves — splitting a restaurant bill, checking a GPA before registration closes, working out whether a stacked discount is as good as it sounds, or counting the working days to a deadline.

How it works

There is no backend. Each page is plain static HTML, and the calculators are small JavaScript components that run entirely inside your browser. Nothing you type is sent to a server, because there is no server to send it to — only a static file host.

The arithmetic lives in separate, unit-tested functions rather than being tangled up in the interface, which is how we keep edge cases like leap years, month-end dates and rounding to the nearest cent from quietly going wrong.

What you will find here

• Tip Calculator — Work out the tip, the total and everyone's share.
• Age Calculator — Find your exact age and the day of the week you were born.
• BMI Calculator — Body mass index in metric or imperial, with the healthy range.
• Loan Payment Calculator — Monthly payment, total interest and the cost of paying extra.
• GPA Calculator — Turn letter grades and credit hours into a GPA.
• Percentage Calculator — Every common percentage question, with the working shown.
• Discount Calculator — Find the sale price, your saving and the real discount.
• Date Calculator — Add or subtract time, or measure the gap between dates.
• Compound Interest Calculator — See what savings grow to, with regular contributions.
• Scientific Calculator — Trig, logs, powers, roots and memory, with keyboard support.
• Fraction Calculator — Add, subtract, multiply, divide and simplify fractions.
• Random Number Generator — Pick random whole numbers or decimals in any range.
• Triangle Calculator — Solve any triangle from three sides or angles.
• Standard Deviation Calculator — Mean, variance and standard deviation of a list of numbers.

More are planned. The site is built so that adding one is a small, contained job rather than a redesign.

Accuracy

The formulas are documented on each calculator page so you can check the working rather than take our word for it. That said, conventions differ: schools weight GPAs differently, shops stack discounts differently, and tipping norms vary by country.

These tools are for general information. For anything that carries legal, financial or academic consequences, confirm the figure with the institution that will actually be using it.

Privacy in one sentence

We do not ask for an account, we do not collect personal information, and the numbers you type never leave your device — the full detail is in the privacy policy.

Get in touch

Found a bug, disagree with a formula, or want a calculator that is not here yet? The contact page has the details. Corrections are genuinely welcome.