Calculators
Every calculator on CalcoraBase runs in your browser, shows how the answer was reached and explains the formula behind it. Pick a category or jump straight to a popular tool.
Categories
- Math calculatorsPercentages, fractions, ratios, factors, primes, powers and more.
- Everyday calculatorsDiscounts, tips, sales tax, unit prices, grades, GPA and random numbers.
- Money math calculatorsCompound and simple interest, loan payments, APR vs APY, savings goals and margins.
- Geometry calculatorsArea, perimeter, volume and surface area of 2D shapes and 3D solids.
- Statistics calculatorsAverages, spread, probability, permutations and combinations.
Popular calculators
- Percentage CalculatorFind X% of a number, what percent one number is of another, or the whole from a part.
- Fraction CalculatorAdd, subtract, multiply, divide and simplify fractions and mixed numbers.
- Area CalculatorArea of rectangles, triangles, circles, trapezoids, sectors, polygons and more.
- Average CalculatorThe mean of any list of numbers, with the sum, count and median.
- Discount CalculatorSale price and savings after a percentage discount, including stacked discounts.
- Scientific CalculatorTrig, logs, powers, roots and factorials with correct order of operations.
- GPA CalculatorCredit-weighted grade point average on the standard 4.0 scale.
- Age CalculatorExact age in years, months and days, plus total days and next birthday.
How our calculators work
Each tool uses the same tested calculation library, runs entirely on your device and never sends your numbers anywhere. Inputs are validated as you calculate, so a typo produces a clear message rather than a wrong answer, and results are rounded sensibly — you will see 12, not 12.000000000000002.
Below each calculator you will find the formula in plain notation, at least one worked example you can check by hand, and notes on edge cases such as zero, negative numbers or rounding. If you want to understand the idea rather than just get a number, the formula reference and guides go into more depth.