Calculators that just give you the answer

What is CalcSuite?

CalcSuite is a growing collection of free, no-nonsense online calculators. Every tool is fast, works on any device, and needs no account. You enter your numbers and get a clear answer in seconds. Each calculator is backed by a transparent formula so you can see exactly how the result was reached, not just a black-box number.

Health & Fitness

The Sunbathing Calculator tells you how long you can safely stay in the sun. It combines your Fitzpatrick skin type, the SPF of your sunscreen, and the current UV index into a single formula, max safe time = (skin type base × SPF) ÷ UV index, and pulls live UV data from Open-Meteo for your exact location so the result reflects what the sun is actually doing right now.

The Calorie Calculator finds your daily calorie needs using the Mifflin-St Jeor equation, then scales it by your activity level to get your total daily energy expenditure. The BMI Calculator computes body mass index (kg ÷ m²) and places it in the WHO weight categories. Alongside them, the Water Intake Calculator sets a daily hydration target from your weight and activity, and the Pace Calculator converts between running pace, speed, time and distance.

Study

The GPA Calculator turns your letter grades and credit hours into a grade point average on the standard US 4.0 scale, GPA = Σ(grade points × credits) ÷ Σ credits, with weighted honors and AP/IB support.

Coming Soon / Roadmap

Four tools are in progress. A Body Fat Calculator will estimate body fat percentage from simple tape measurements, a Vitamin D Calculator will work out the minimum sun exposure needed to hit your daily synthesis target, and a Sunscreen Timer will tell you when to reapply, accounting for water and sweat. For students, Flashcards will turn your notes into a study deck. Our goal is simple: give you the numbers you need in seconds so you can get on with your day.